When the Minnesota Twins traded Ben Revere to the Philadelphia Phillies, they acquired one pitcher who can help the team immediately, Vance Worley, and another who is expected to contribute in the future in Trevor May.
Because Worley is the known commodity who will be a member the starting rotation right away, let's focus on him first and breakdown May next week.
Affectionately known as "Vanimal" to the Phillie fan base, the 25-year-old Worley wound up being the fifth starter on a team whose rotation featured a stable of prized horses including Cole Hamels, Cliff Lee and Roy Halladay. On an average team, he's likely a three or four-type starting. In the depleted staff in Minnesota however, until some additional moves are made this offseason, he could very well could be the second-best starter on the team.
On the surface, Worley is very much a pitcher who fits the Twins' mold: He throws strikes, he works ahead in the count and he pitches to contact. In fact, his 5.5% swinging strike rate last year was the third-lowest rate among all starters with a minimum of 130 innings pitched. That total fits in well with the Nick Blackburns of the world.
Of course, the biggest difference was that Worley was still able to strike people out even if he couldn't get them to swing-and-miss. His 18% strikeout rate last year would have finished ahead of everyone in the Twins rotation save for Francisco Liriano.
So, if he's not getting hitters to miss, how did he accumulate so many strikeouts? Jedi mind trick?
In 2012 Worley's strikeouts were largely a product of hitters failing to pull the trigger. As mentioned before, his swinging strike rate was well-below the major league average therefore he relied on painting corners and hitting his location. This past year, according to Baseball-Reference.com 57% of Worley's strikeouts were of the looking variety. That mark was the highest among all qualified pitchers and surpassed the baseball average of 24%. In fact, no other qualified pitcher had more than half of their strikeouts looking.
Interestingly enough, a higher amount of his strikeouts came against opposite-handed hitters rather than same-sided ones. Over his career, in the exact same number of plate appearances against both sides (597), Worley out-whiffed lefties (134) over righties (103). These reverse splits are related to the fact that he has caught more hitters looking versus getting them to swing and miss.
Worley's main weapon of choice against lefties is his sinking two-seam fastball. When he finds himself in a two-strike count, he will dial up this pitch more often than any other (40% of the time with two-strikes). This downward and glove-side run of this pitch combined with his excellent placement has allowed him to aim it at the hitter's belt and watch it fade back over the plate, like this:


The location and movement of this sinking two-seamer freezes opponents in their tracks. According to his profile at BrooksBaseball.net, with two-strikes, Worley has gotten strike three looking on this pitch 20% of the time he throws it.
Perhaps because of his tendency to ride a pitch on their hands or throw soft stuff away, left-handed hitters had a difficult time pulling Worley. Possibly due to necessity of avoiding Citizens Bank Park's inviting right field stands, he was able to keep hitters from going that direction often -- instead redirecting them back up the middle or to the opposite field. Unfortunately, Worley's ability to do the same against right-handed opponents was non-existent as he was decisively average in his directional splits. The idea that a pitcher can control where a hitter hits the ball is debatable however if he is able to repeat this skill, the ability to keep hitters to the big park of the field, specifically at Target Field, so be beneficial**.
**Then again, the Twins just traded away two very solid defensive center fielders and could employ a "Balls-To-The-Walls" defensive alignment in the outfield.
Another interesting component of his game is the way that he has kept the ball in the park despite pitching in a very hitter-friendly ballpark.
In his short career, Worley has allowed just 0.75 home runs per nine innings while the rest of the league has been closer to 1.00 HR/9. What makes this feat even more impressive is that Philadelphia's Citizens Bank Park, known for its home runs and quick-taze security guards, has been a home run haven. Left-handed hitters, in particularly, have thrived there. According to StatCorner.com, the CBP has a Home Run Park Factor of 126, well above the neutral of 100. For comparison, Target Field vastly decreases the amount of home runs by left-handed opponents, carrying a 76 Home Run Park Factor. In theory, the transition to the home run-suppressing Target Field should help keep his home run rate down while switching to a league with an added offensive player in the lineup.
So all of this seems positive. Yes, there will be some statistical inflation when he switches from a league in which he gets to face a pitcher holding a rolled up newspaper every ninth man up but his methodology and new environment should be able adapt quickly.
The concern, however, is the health of his elbow.
This past August, Worley would be shut down due to "loose bodies" in his throwing elbow and have season-ending surgery. While these procedures are described lightly and often referred to as "clean up" by teams, they can be symptoms of more ominous issues inside the elbow. The aforementioned Blackburn, who once had similar movement on his sinker, required this procedure in order to clean out some "loose particles" in his elbow in October 2010. Since then, Blackburn has been on-and-off the DL, had more surgery and has pitched with almost zero effectiveness. Like Blackburn did, Worley relies on touch and finesse which is provided by a healthy elbow.
Now, that is only a disclaimer. Focus more on the fact that Worley has strong ground ball skills, ability to get strikeouts without needing to getting hitters to miss and is still young enough to be a part of the rotation for several years. In all, I say the Twins landed themselves a decent middle-of-the-rotation arm.