The Twins have invested over 100 million dolars in their pitching rotation buying 8 seasons of starting pitching. What can they expect for their $100,000,000?

I started with Ervin Santana looking for a similar group. From ages 27-31 he has performed at a 99 ERA+ with about 1000 innings pitched. I wondered how other groups of pitchers performed from ages 27-31. With the help of BR's play index, I searched for all pitchers since 1975 who have pitched at least 900 innings in their age 27 through 31 seasons. There are 128 pitchers headed by Pedro Martinez and his 228 ERA+ through ages 27-31. The top is loaded with current or future Hall of Famers. I won't be comparing Santana to them.

Time for a little sidetrack.

Why ERA+? I used ERA+ to adjust for era and ballpark. While a single season of ERA does not predict future ERA as well as FIP or xFIP, a sample size of around 1000 innings does a good job. At that sample, it is more likely to wonder why a players FIP is far different than his ERA and speculate which skill set caused them to outperform or underperform their FIP. For the whole group, it didn't surprise me that the FIP and ERA were within 2% as FIP is supposed to project ERA.

Another note on FIP. I looked at players who had FIP over those 5 years significantly different than their ERA. Ricky Nolasco and Ervin Santana can be found at different end of that spectrum. Nolasco has a far better FIP (3.75) than ERA (4.51) and Santana has a better ERA (3.88) than FIP (4.21). Should the Twins hope on Nolasco's FIP while at the same time ignore Santana's? Though FIP might indicate otherwise, I suspect Santana is the better pitcher and ERA at this sample size can be trusted at least equally with FIP.

Sidetrack#2

Ricky Nolasco is in the list. He ranks 127 out of 128 with his ERA+ of 87 from ages 27-31. I can't come up with a good comp group for Nolasco. Very few pitchers can pitch at below a mid #4 starter through their peak seasons and be given the ball enough times to gather at least 900 innings. Even if his poor 31 year old season is thrown out and ages 26-30 are used instead, you get a 90 ERA+. That moves him ahead of Jaime Navarro for the 126 spot on the list.

Sidetrack#3

I was surprised to see Dennis Martinez at number 128. He had a very interesting and unexpected career after age 31. At 32 he was traded with a player to be named laster (catcher John Stefaro) to the Expos for a player to be named later in Rene Gonzalez. The Orioles had essentially given him away. Martinez was named to the first of 4 all star games at age 36 and pitched until he was 44. I am not sure what he changed once he joined the Expos but walks were down, strike out were up and hit batsmen were way up after the trade.

Sidetrack#4

I had play index help set levels for starter numbers. I looked at over the last 10 seasons (and 1500 pitchers with the most starts per season) and sorted starters by ERA+ grouping them in sets of 300. The 150th rank should be the mid of the number 1 starters. Starters ranked around 300 would be strong #2/fringe #1 starters. I have done this before and the results were similar.

Number ERA+

#1 133 (121- )

#2 114 (107-121)

#3 100 ( 95-107)

#4 90 ( 84- 95)

#5 76 ( - 84)

So a pitcher like Nolasco had the performance of a number 4 starter at the time the Twins signed him.

Back to Ervin Santana.

Of the 128 pitchers in the group, Santana ranked 106 with an ERA+ of 99. The 99s ran from 106-111. That isn't very exciting as a rank but it is possible to build a group of pitchers on both sides of his performance. I chose a group that included 16 pitchers below and above him. They had ERA+ ranging from 95 to 103. The group can be found here

I then had to throw out some of the pitchers. I don't know how Jason Vargas will perform after age 31. He is the same age as Santana. Some guys like Rick Langford, Erick Hanson or Russ Ortiz were injured in their age 31 season. Theie careers were over as a result. One guy was in prison.

I kept Mike Scott and Dave Stewart though they had significantly better age 31 seasons and would probably earned a contract somewhere around Lester.

It would be really nice of I knew how to do tables. The image above is a picture of a table. Not sure if it is a link or picture. The results can also be found on sheet 2 of the google doc.

Essentially of the remaining 26 pitchers in the group 13 performed with an ERA+ of 94 or better and 13 below. I think it is reasonable to expect Santana to perform as a number 3/4 starter next year. The group changes to size 25 at age 33 as Eckersley became a closer. There number of pitchers that performed at or above 94 is now 10 and there are 11 pitchers either did not pitch or would be classified as a number 5 pitcher. The median is a number 4 pitcher with a 40% of the group performing better. The median drops to number 5 starter at age 34 and not starting at age 35.

How will Santana Perform?

If Santana follows the age curve of similar pitchers the Twins might expect for him to start as a fringe #3 next year and decline to a #4, #5 and possibly the bullpen in the following years. There is hope that at age 34, 32% performed at least at an ERA+ of 94. The number drops to 16% at age 35 but it isn't 0%.

Nolasco doesn't have enough comps that have pitched similarly. They have one bad season out of him. Is it reasonable to hope that they will get a number 4 and maybe a number 5 out of him in the next three years. Maybe not.

2016 and Beyond

It looks as if the Twins can hope to have filled their number 4 and 5 pitching slots in 2016 with their $100,000,000. They just to fill in the top 3. Let's hope it comes from Hughes, Meyer, May, Gibson or Berrios. That is a lot to expect of a young pitcher. It might be better to sign a top of the rotation guy and fill the 4-5 slots with young pitchers struggling to adjust to the majors. As for 2017, they really need those young pitchers to adjust quickly so they have the pitching to back up the young hitters. They could have a lot of money committed to two guys fighting for the number 5 spot.