Article: Eddie Rosario And The Battle For Plate Discipline

[Jamie Cameron]

Eddie Rosario has always been a polarizing player for me. In his first extended stint with the Twins in 2015, he showed flashes of a really exciting all-round game. He was a good base runner (4.7 runs above average), a solid defender (2.2 runs above average), and clobbered 13 home runs in his age 23 season. Rosario had excelled throughout five minor league destinations, and was noted for having an exceptionally quick bat and hands. There were a few major problems. Rosario struck out a lot (25% in 2015, compared to a league average 21%) and he rarely walked. Like, ever. In 2015 Rosario walked just 15 times in 474 plate appearances, good for a BB% of just 3.2%, well below the league average of 8.1%. Taken together, Rosario’s strikeouts and inability to take a walk amounted to cripplingly poor plate discipline.In 2016, some of the aspects of Rosario’s game which made him exciting disappeared. His base running regressed marginally in 2016, and majorly in 2017. His defense went from good in 2015, to acceptable in 2016, to pretty bad in 2017 (-6.2 runs above average), a dip not often discussed in the Twins heralded 'Nothing falls but raindrops’ outfield, which should be renamed to reflect the fact that anyone not named Byron Buxton is actually a poor to average defensive outfielder.

 

Rosario’s regression and streaky hitting were so infuriating that it led to discussion about whether he would be the odd man out in the Twins up-and-coming outfield moving forwards, with Buxton spectacular, Kepler solid, and Zack Granite pushing for playing time with an impressive season at Rochester. Throughout his first two seasons, Rosario had shown little progress in his plate discipline, leading folks to voice the possibility that he had hit his ceiling. Enter James Rowson.

 

If Pat Shurmur is the MVP of the Vikings this season, Rowson deserves the same plaudits for his work with Buxton, Polanco and Rosario in 2017. In researching Rowson, two things seem to stand out about his approach with the young core of Twins hitters. First, he wants players to have a high comfort level in taking ownership of their own swings. Second, he’s keenly aware of the strengths and weaknesses of his hitters and publicly pushes those buttons. After a game against the White Sox, Rowson named Rosario the player of the game, despite going 0-4, crediting him for helping teammates see more pitches from Jose Quintana which eventually allowed them to force him from the game.

 

Rosario’s numbers from 2017 are a testament to Rowson’s work. He increased his BB% to just under 6%, taking 23 more walks than he did in 2016. Rosario’s OBP jumped almost 30 points, despite a 26 point decrease in his BaBIP from 2016 to 2017. The main cause for this increased ability to get on base? Rosario was significantly more selective with his swings in 2017. He dropped his O-Swing % (the percentage of time he swings at pitches outside the strike zone) from 42% to 37%. This decreased his overall SwStr% around 5% and led to a significantly increased Contact% (percentage of the time a hitter makes contact when swinging at all pitches). Overall, Rosario wasn’t swinging at significantly fewer pitches. He's swinging at significantly more hittable ones, leading to a spike in home runs, walks and isolated power.

 

Entering his final pre-arbitration year in 2018, Rosario will need to keep his improved offensive output going to offset other diminishing skill sets. If Rosario can continue to build upon his improved plate discipline in 2018, he could finish the season as one of the more offensively productive outfielders in the American league.

 

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[mikelink45]

The defensive regression is the part that worries me the most.  In his first full year his throws and speed were really assets and he looked to be an above average OF.  What happened?  Can he only concentrate on one aspect of the game at a time?  

[caninatl04]

I concur- any deep dive on his defensive numbers?

[jorgenswest]

Jamie-The walk and strike out rates as well as the O-Swing likely indicate growth in Rosario’s skill level. I appreciated that you stayed with numbers where the sample likely shows a change.

 

Mike- I worry about defensive metrics also. However, they have the stability of slash stats at a season level and can vary significantly from one season to the next. It is just as likely the change in defensive metric is random variation due to sample as regression. Watching him, I am left with the impression that he makes the mistakes of throwing to the wrong base sometimes trying to do too much than he can do and sometimes it seems to be lack of focus. I don’t have data to back it up though. There must be some detailed Statcast data that can better answer that question.

Edited January 3, 2018 by jorgenswest

[diehardtwinsfan]

I'm not sure I buy the defensive regression. He seemed to be the victim of the occasional boneheaded play, but that's a far cry from being a poor defensive OF. 

 

Defensive metrics are not very good, for one, but there's also evidence that one fielder gets punished when you have two other very good defensive OFs. Rosario can play CF, so his problem certainly isn't range.

 

Back to Eddie, he was one of the big reasons we made the playoffs. Given his age, it's not unreasonable for him to make a step forward... and he was well above average for mlb last year.

[T_J]

Rosario is my favorite current Twin. Watching him play he seems to actually care about outcomes of every game. He just has that look in his eyes. I was at a game against the Padres this season and I watched him steal third and take home on a bad throw. In extra innings he came up to bat and I leaned in and told my poor old mother that wasn't enjoying the bonus baseball (Seriously, why go to a ball game if you're going to complain about getting free baseball!!!!) that his at bat was going to be the last one of the game. I said Eddie is going to be the hero for the night. He ends up doing it. Blasting a walk-off. To me, he just has that "it factor" when it comes to wanting to win. 

[mikelink45]

 

I'm not sure I buy the defensive regression. He seemed to be the victim of the occasional boneheaded play, but that's a far cry from being a poor defensive OF. 

 

Defensive metrics are not very good, for one, but there's also evidence that one fielder gets punished when you have two other very good defensive OFs. Rosario can play CF, so his problem certainly isn't range.

 

Back to Eddie, he was one of the big reasons we made the playoffs. Given his age, it's not unreasonable for him to make a step forward... and he was well above average for mlb last year.

I miss the strong arm and the way he impacted the game with those throws as a rookie.  Now I have more of a fear than anticipation, wondering if he will throw to the right base.  He has more talent on defense than he was showing last year. 

[Darius]

I can't recall a more entertaining player to watch than Rosario on his massive hot streak in July/August. That was about as good as it gets.

[bdodge22]

Jamie- I haven't seen you post on TD before. Nice article! Thanks for writing!

[markos]

 

Jamie-The walk and strike out rates as well as the O-Swing likely indicate growth in Rosario’s skill level. I appreciated that you stayed with numbers where the sample likely shows a change.

Mike- I worry about defensive metrics also. However, they have the stability of slash stats at a season level and can vary significantly from one season to the next. It is just as likely the change in defensive metric is random variation due to sample as regression. Watching him, I am left with the impression that he makes the mistakes of throwing to the wrong base sometimes trying to do too much than he can do and sometimes it seems to be lack of focus. I don’t have data to back it up though. There must be some detailed Statcast data that can better answer that question.

I'm not sure this exactly answers your question, but this is my current analysis of Rosario's defense:

 

When Rosario was first called up, I also assumed that he was a legit centerfielder that would be a real asset in the corners. But I've changed my mind for a number of reasons. It is easy to dismiss defensive stats, especially in small samples (though the statcast data may actually turn the corner on this - too early to tell). But with Rosario we almost three full seasons of data that tell a pretty consistent story. Further, it is backed up by some of the statcast metrics.

 

- Statcast has been tracking the sprint speed of players for the past three seasons. Rosario's sprint speed readings have deteriorated every single season. His speed is no longer close to the average centerfielder and is barely an average corner-outfielder. He is slower than the almost-34 Denard Span, and he matches up close to guys like Justin Upton, Michael Conforto, and Aaron Judge.
- Every single defensive metric (UZR, DRS, Statcast Outs-Above-Average, FRAA from BP, Clay Davenport) agreed that Rosario was somewhere between average and below-average last year.
- If you pull out his arm statistics from 2015, every single metric throughout his entire career has agreed that Rosario is average-at-best when it comes to making plays.
- I don't watch a ton of games, but this matches my eye test. Looking at the facets of outfield efficiency (first step, raw speed, route effiency, judging the wall, glovework), I can't say that I think Rosario is definitely above-average in any area. Don't get me wrong, I don't think he isn't bad in any area either. Just kind of average. Given his average raw athleticism, I think it is hard to make an eye-test case that he is above-average.

 

Projecting forward, I think there are signs of concern: there is evidence that defensive ability peaks in the early-twenties - Rosario is now 26 - and his sprint speed has already decreased three years in a row. If those trends continue, I wouldn't be shocked if he settles in as a below-average-but-not-dumpster-fire outfielder by the time he reaches free agency. Something like 5-15 runs below average per season - i.e. more Melky Cabrera than Brett Gardner.

[yarnivek1972]

Any theory that Buxton kinda being a ball hog might negatively impact Rosario’s range metrics?

[jmlease1]

I don't think there's any question that Rosario's defense has declined from his rookie season (I'll debate the idea that Buxton is the only quality defender out there, however; Kepler is still a good defender and Granite certainly has potential). But if he can keep up the increased discipline he showed last season, he's a useful player. He doesn't need to be a walk-taking machine, just show an understanding of the zone so he doesn't get himself out.

 

It's also possible that he can improve his defense back up to something closer to average out there if he's established a more consistent approach at the plate. he's got the arm to be a nice corner OF and enough range to get to the balls he needs to, but he makes poor decisions out there. well, he made poor decisions at the plate two years ago and that improved.

 

He's not super young any longer, but maybe he's matured? I'm rooting for him, that's for sure.

[Mr. Brooks]

Many dismiss it, but the poor baserunning is a concern for me.

Hopefully the coaching staff can work with him on that this year.

[nicksaviking]

Seeing as defensive metrics don't and can't measure whether or not the manager has instructed him to be overly aggressive trying to throw out runners I'm not putting a ton of weight on numbers assessing his arm. Throwing behind the runner can be fixed, trying to nail guys at the plate instead of cautiously tossing it to 3B could just as likely be on the coaches as it could be on the player.

[Jamie Cameron]

Thank you! First one from me, more to come!

 

Jamie- I haven't seen you post on TD before. Nice article! Thanks for writing!

 

[RaymondLuxuryYacht]

I agree with dodge - nice post.  Thank you for writing.

[Jamie Cameron]

Much appreciated! Super excited to be part of this community and meet the great people in it!

 

I agree with dodge - nice post.  Thank you for writing.

 

[Doomtints]

Usually I would be a skeptic of a small sample size change, i.e., being a bad defender for a year. But dang, Rosario was bad last year, and a drop off this steep is a concern. He does not hit anywhere near well enough to defend this poorly.

 

There is no question the Twins are going to have him work on his defense next year. If he can be an average defender again and keep improving offensively, he's a 3+ bWAR guy.

Edited January 4, 2018 by Doomtints

[Thrylos]

I'd actually offer a contrarian opinion here:

 

If someone can hit .300, with close to 30 HRs and only a 18  K%, I don't want him to take walks

 

That was Rosario's 2017 season.    He, (and Polanco 7.5 BB% and 14.3 K%) should be swinging the bats.   It works.

 

Because of the title: Rosario, based on his K%, does not have much of a problem with plate discipline...  Has lower K% than Dozier, Buxton, Kepler, Sano, Vargas, etc....

Edited January 4, 2018 by Thrylos

[Linus]

He has the tools to be a good corner outfielder-sufficient speed and a strong arm. This is all part of the development process so I think it is premature to judge him as a fielder.

[BJames]

Agree with Thrylos.  The guy just hit 33 doubles, 27 Hr's, .290 Avg, .507 Slg and and OPS of .836. in his 3rd full year.  I just hope Buxton and Kepler can improve the same way. At this point his defence is just not that big a deal compared to what he can do with his Bat!  Keep it up Eddie!

[Brandon]

Is he slower than Kepler at this point? Maybe he should be a RF instead and Kepler in LF.

[Brandon]

I just go with the flow on offense with him. He does need to hit for average though cause the scouting reports all say he doesnt have elite power....but 25 HR is more than enough with a .280 average.

[Tommygun921]

When Rosario is on, he's one of the better players in the league. This is why I always hate seeing people mention him as a trade possibility. He WILL come back to bite us if he gets traded. I also think alot of his defensive decline had to do with bone headed plays. Combination of Delmon Young's bobbles and Carlos Gomez's poor throws. Seems like some easy things to fix. I think he is just overly confident in his abilities at times. Thinking he can gun someone down when he should just be hitting the cutoff man.

[Twodogs]

I just wanted to chime in on an experience that I had with Rosario this past summer. This has nothing to do with his abilities nor does it have anything to do with his stats. We were at Petco field on August 2nd, I live in California, we were in left field probably about 10 or 11 rows back. I was wearing a 1984 powder blue Kirby Puckett Jersey, my 7 year old son was wearing his Byron Buxton Jersey, my 4 year old daughter was wearing a Joe Mauer jersey and my sister was wearing just a plain Twins Jersey. So we were cheering for the Twins the whole game. Not to mention this is about the time the twins kinda turned it around as they had his a little slump at the end of July. Rosario had made a nice catch to save extra bases earlier in the game, prob 6th or 7th inning and we were cheering. Bottom of the ninth comes along and Buxton and Kepler are warming up together and Rosario and the Padre's foul line person are warming up. While the Twins closer was warming up on the mound. Anyway all game long, Rosario would throw the ball back to the Padre's employee and turn around and get ready to play. This time however, he waves her off and turns towards the crowd in left. He points right at my 7 year old son, Max puts his glove up, he plays on a 9 - 10 year old travel ball team so he can catch just fine and is ready. Eddie throws the ball; it is headed right for my sons glove, then a heavy set bald dude with a Padre's jersey jumps up and tips the ball. The ball ends up about two rows behind us and in the section across the aisle to our left. Eddie looks at the guy who caught the ball, points at him, then points to Max, points at the guy again and then points to Max; like that ball was meant for him. He did that about 3 times and the guy comes over and gives my son the ball. The crowd cheered a little and Eddie turned around and finished off the game. My only contribution to this article is that Eddie Rosario made a fan of himself that day. Obviously I recognized the significance of what he did, but so did my son, and so did my daughter actually as she made me buy her a ball in the souvenir shop after the game so she could also have a ball like her brother. Anyway, Eddie is a good guy and I hope that he keeps progressing and becomes one of the Twins all time greats.

[diehardtwinsfan]

that's a really cool story.

[Kelly Vance]

I remember Eddie's debut season. He homered in his first AB (which foreshadowed a clutch ability)  and through the year he was tested time after time (he was a rookie after all) by base runners and he gunned down a lot of guys. Outfield assists are relatively rare, and I liked his confidence. Last year, he seemed to want to repeat his success a few more times than I would have liked. Time and coaching will fix that.The thing is, he raised his BA to .290 and hit 27 homers.Even giving lip service to a regression on defense, how in heck does that make him a below average outfielder? But for me, what I like about Eddie is that he is clutch. I don't have stats on this but when I see him come up in a pressure  situation, I feel like he is going to make something happen. Almost as confident as when Joe comes up.  In the WC game, I expected a homer in that at bat, and he came through.  I guess count me as one who sees real potential in this kid. I think he can be a special player, given time. 26 is not that old. 

[Shane Wahl]

This is a great article. Wow. More later on that. Anyway, I actually think that the Twins should switch Rosario and Kepler in the OF. I don't know if that has been suggested on the site, but it makes a lot of sense to me. 

[Shane Wahl]

The key is for him to stabilize this production at the plate. All of his minor league stats up to AA make that a real possibility. I trust that he will become a better defender.

[Doctor Wu]

 

I just wanted to chime in on an experience that I had with Rosario this past summer. ... Anyway, Eddie is a good guy and I hope that he keeps progressing and becomes one of the Twins all time greats.

Reading stories like that remind me of why I love baseball. And very good article, by the way!