2015 Phillies Report Card: Jake Diekman
When I evaluated Jake Diekman‘s season last year, I gave him an A- on the strength of unmistakable strikeout prowess. In 2014, Diekman struck out 100 batters in 71 innings, and finished the season seventh in the majors in strikeouts among qualified relief pitchers. He made a lot of appearances, ninth in the National League in that category. Manager Ryne Sandberg showed no mercy on the lefty, and also exposed Diekman by having him face too many righties. Though his strikeout numbers were elite, he had a 1.42 WHIP and a 104 ERA-, both of which were bad enough to place Diekman in the bottom quartile of relievers. In my 2014 report card, I argued that if Sandberg protected Diekman a little bit more in 2015 and didn’t have him face so many righties, it would help Diekman take the next step.
Welp. In 2015, Diekman had a 1.75 WHIP with the Phillies in 36.2 innings. Even with a 0.92 WHIP in 21.1 innings as a Ranger after going to Texas in the Cole Hamels trade, Diekman’s 1.44 WHIP at the end of the season was the 14th-highest among qualified relievers. That’s a poor season, but it still seems fascinating to me considering Diekman’s great finish with the Rangers. After two full seasons in the big leagues and four years overall, Diekman has a career 1.44 WHIP. Nevertheless, I still believe in his stuff and his ability to become one of the game’s better relievers. In a two-month sample in the heat of a Texas pennant race, Jake Diekman showed how good he can be, and how impactful coaching and usage can be for relief pitchers.
Statistically, 21.1 innings in two months is meaningless in the context of Diekman’s 195 career innings. As with any type of ballplayer, relievers have ups and downs throughout seasons or across multiple seasons. But the dramatic difference in Diekman’s performances in Philadelphia and Arlington is undeniable, and is a reminder that, as brooksbaseball.net says, Diekman has electric stuff:
His sinker generates an extremely high number of swings & misses compared to other pitchers’ sinkers, is thrown at a speed that’s borderline unfair and has slight armside run. His slider generates a high number of swings & misses compared to other pitchers’ sliders, results in many more groundballs compared to other pitchers’ sliders and is much harder than usual. His change is thrown extremely hard, generates an extremely high number of swings & misses compared to other pitchers’ changeups, is a real worm killer that generates an extreme number of groundballs compared to other pitchers’ changeups, has an obvious armside fade and has some natural sink to it.
With the Phillies in 2015, Diekman’s performance was terrible. Then, as a Ranger, he somehow became a deadly weapon.
So what happened? Well, Diekman cut his walk rate almost in half and saw his strand rate spike. His ERA- and BABIP fell off a cliff. But how, exactly, did Diekman produce such dramatically different results? Was it the change of scenery, leaving baseball’s worst team for a clubhouse jockeying for a postseason berth? After all, Diekman is from Nebraska. Maybe he just really didn’t like playing in Philadelphia and felt more comfortable closer to home. Maybe it was the Mike Maddux Magic? The Rangers pitching coach, perhaps, breathed his Maddux dust onto Diekman and changed him overnight. Maybe some or all of that helped.
But beyond the Land of Narrative Speculation, the Phillies saw a flaw with a player they scouted, drafted, and developed, and they fixed him. Diekman was sent down to the minors in June for two weeks, and was advised to adjust his arm slot to create more movement on his pitches. As much as Ryne Sandberg deserves criticism for overusing Diekman and his pitching staff as a whole, the Phillies deserve credit for knowing their players. But the Rangers saw something too, because after going to Texas, Diekman threw more sinkers and fewer sliders. He lost some strikeouts along the way, but generated more ground balls.
In 2015, Jake Diekman threw his fastball with an average velocity of 96.5 miles per hour (the same as Ken Giles). Diekman has nasty pitches, and is not as bad as his performance with the Phillies indicates. He was a painful but necessary addition to the Cole Hamels trade, and I believe Diekman can translate his arsenal of pitches into an elite season in 2016. As for 2015, the results are obviously mixed. There’s no denying his poor performance with the Phillies, just as it’s impossible to ignore his dramatic improvement with the Rangers. I’m grading Diekman on his performance, but also on his ability and potential. Call me a sucker, but I’m not ready to give up on Jake Diekman yet.