Iwasatgame6

Spring training has begun, and the season is right around the corner. The start of the season begs the age-old question, who is the Opening Day starting pitcher?
The Twins have never spent significant money or pushed all their chips in to acquire a true "ace," which has left the spot of Opening Day starter as a revolving door of pitchers. The Twins have used three different pitchers in the last three years and eight different in the past ten years. 
This year, however, the Twins are in a different situation. While they still don't have a real #1 that so many desire, they have five starters that all could reasonably start on Opening Day. Who's the most likely to get the nod?
The most significant deciding factor is, more than likely, health. This past season, Sonny Gray was presumed to be the Opening-Day starter after his March 13th acquisition, but he was behind pace in spring training, and the honor was given to rookie Joe Ryan. 
It's possible that a similar situation may take Tyler Mahle out of the running. Mahle was acquired at last year's deadline but threw just 16.1 innings with the Twins before his season ended due to shoulder injuries. As of now, Mahle's spring training is going normally, but it is something to monitor as we head toward Opening Day. His upside is arguably the highest in the rotation, but he's only had one above-average season in his career. His lack of consistent performance and last year's injury makes him the least likely of the four to start on Opening Day.
While he isn't a definitive #1, Pablo Lopez substantially raises the rotation's floor. His talent is similar to Sonny Gray's, and he has shown that he can be a workhorse-type pitcher, throwing 180 innings this past season. Lopez is pitching in the WBC for Venezuela, so his performance and health may dictate his chances for Opening Day. He is also brand new to the Twins, and teams tend to pick veteran starters with more experience on the team, so it may limit his chance to start Opening Day.
Kenta Maeda is clearly another candidate. He was the Opening Day starter two years ago in 2021, coming off a (shortened) season in which he finished second in the American League Cy Young Award voting. But last year was a lost year for him as he worked his way back from Tommy John surgery. That doesn’t necessarily disqualify him, but there are more worthy candidates.
That leaves the two front-runners: Joe Ryan and Sonny Gray. In 2022, Ryan became the first Twins rookie to start on Opening Day since 1969. Ryan was solid with a 2.2 WAR and a 109 ERA+. He also showed his durability by leading the team in innings pitched with 147. He has no history of substantial injuries and will be ready to go on Opening Day. His lack of a track record of successful pitching is the only thing holding him back. 
Sonny Gray proved his spot as the #1 last year with 2.4 WAR and a 125 ERA+. While he did land on the IL three times, he finished the season with no injuries. Gray is the veteran of the four at 33 years old and has already pitched an entire season for the Twins. Gray has been in the league for a decade and has shown his ability to perform consistently year after year. He also has a reputation in the clubhouse as a team leader.
After looking at team history, previous injuries, and other factors, all signs point to Sonny Gray starting Opening Day. Gray has already pitched in live BP down in Fort Meyers and has no limitations in spring training. His previous time with the Twins and his veteran talent make him the strongest candidate to start on Opening Day. 

Pitching in today's game is more advanced than ever. Fastballs are faster. Breaking pitches break more. All of that leads to pitching being more exciting than ever. The Twins are no stranger to this, as their staff has some of the nastiest stuff in the league, but who truly had the best pitch on the Twins in 2022? 
To measure, I am using Run Value (RV). Run Value looks at run expectancy in each unique situation and how a specific pitch affects that run expectancy. Run Value is through the eyes of the pitcher, so a negative number represents a good pitch because it lessens the chance of a run and vice versa. It is important to note that run value is an accumulative stat, meaning that the more innings someone pitched, the more RV they can acquire, and now on to the top ten.
10: Griffin Jax's slider: -7 RV
9: Sonny Gray's curveball: -7 RV
8: Jovani Moran's changeup: -7 RV
7: Caleb Thielbar's four-seamer: -8 RV
6: Jhoan Durán's curveball: -8 RV
5: Chris Archer's slider: -9 RV
Archer was largely ineffective last year, with lousy walk numbers, and he didn't go far into games, leading to a WAR of precisely zero. The lone bright spot of his season was the slider, which snuck into the top five. Archer's slider rate ticked up this past season, and for a good reason: it was his only effective pitch. Opponents batted .202 against it, and he got a 26.5 whiff% with his slider.
4: Michael Fulmer's slider: -9 RV
Acquired at the trade deadline, Fulmer's arsenal is slider heavy, throwing it over 60% of the time. He averages 90.3 MPH, which is top ten in the league. He was effective in his time in Minnesota with an ERA of 3.70 and an ERA+ of 106. His slider was a big part of that, as it held opponents to a .342 SLG and had a 24.7 put away%. 
3: Jhoan Durán's four-seamer: -9 RV
Arguably the most dominant pitch on this list, it doesn't rank higher in RV due to the lack of innings pitched. Duran had the highest velocity fastball in MLB last year with an average speed of 100.8 MPH, beating out other flamethrowers such as Edwin Diaz and Ryan Helsley. Topping out at 103.8 MPH and averaging more inches of movement than his curveball, Duran made opposing hitters look lost with a 25.9 K% on his fastball.
2: Sonny Gray's four-seamer: -11 RV
Gray uses his fastball much less than the other top five on the list, at just 28.3%, but his results were just as effective. Nothing instantly jumps out; his velocity and strikeout numbers are average to below average. His opponent slugging however, was .345, 50 points below the league average. Gray's four-seamer has run similar to a two-seamer, and he was able to dominate the left side of the plate. 
1: Joe Ryan's four-seamer: -21 RV
Somewhat of a surprise due to his low velocity, but Ryan's fastball was elite. In terms of run value, that pitch ranked ninth in MLB and the fourth-best fastball, only behind Justin Verlander, Nestor Cortes, and Carlos Rodon. Thrown a whopping 60.1% of the time, it held opponents to a mere .174 batting average. Ryan's lower arm slot makes the pitch look like it's rising, making it especially difficult for hitters to pick up on. 
Joe Ryan and Jhoan Duran should be staples on this list for years to come, but spots are up for grabs. Which new pitches could emerge next year? Which pitches surprised you? Can anyone take Ryan's top spot? Leave your thoughts below!

Recently, the Twins acquired Pablo Lopez plus two prospects in exchange for Luis Arraez. While the trade could be unpopular and controversial within the fanbase, Lopez adds depth to a starting rotation with multiple question marks. 
Looking deeper into Lopez's numbers, you might notice something out of place: he has a drastic home/away split  - and not in the way you might think. Due to familiarity, weather, fans, and multiple other factors, a pitcher's stat line is often significantly improved at home. Take Sonny Gray and Joe Ryan, for example: 
Sonny Gray
Home - 67.2 IP, 2.66 ERA, 10.4 SO/9
Away - 52 IP, 3.63 ERA, 6.8 SO/9
Joe Ryan
Home - 83 IP, 3.04 ERA, 9.8 SO/9
Away - 64 IP, 4.22 ERA, 8.6 SO/9
Pablo Lopez is almost the exact opposite. 
Home - 87 IP, 4.55 ERA, 8.1 SO/9
Away - 93 IP, 3.00 ERA, 9.3 SO/9
Lopez had more innings pitched, a higher ERA and WHIP, and worse strikeout and homerun numbers while playing at his home stadium. Why is this the case, and what could it mean for his time as a Twin?
Baseball Savant uses multiple advanced stats to measure the differences between venues, including Park Factor, wOBACon, and BACON. Lopez’s previous home stadium, the Marlins’ loanDepot Park, ranks about average in all three. loanDepot Park ranks even lower for home runs, in the bottom third in the MLB. There is nothing out of the ordinary to suggest it inherently hurts pitchers. 
All of the loanDepot park factors are irrelevant now as Target Field will be his home field. Target Field favors pitchers slightly more than Miami, suggesting a slight upgrade in home-field production. 
But strength of schedule also appears to play a role in his reduced home numbers. Lopez played in the NL East, arguably MLB’s toughest division. At home, he faced off against NL East rivals four times, along with starts against the Padres, Dodgers, and Cardinals. All the teams that Lopez made home starts against have a combined win percentage of .516. For comparison, the Baltimore Orioles have the most challenging schedule heading into 2023 with a .509 win percentage.  
This should be a problem no more, as the AL Central is arguably the worst division in baseball. The Twins are heading into 2023 with the third-easiest strength of schedule at .495. Instead of multiple games against the Mets and Braves, he gets multiple games against the Royals and Tigers. The Twins will play 26 home division games next year, and assuming health, Lopez will get four or five of those starts. 
Every team and every individual player has their weaknesses, but the Twins are lucky when it comes to Pablo Lopez because there is a simple explanation for one of his glaring issues. Lopez should already see improvements by simply playing at Target Field and in the AL Central. By the end of the season, Pablo Lopez could implement himself at the top of the rotation and become a fan favorite at his new home stadium.