It’s been an interesting ride for the Twins veteran southpaw Glen Perkins. After about a season and a half’s worth of starts back in 2008 and 2009, the organization apparently decided that they had seen enough. Can you blame them? Sure, he suffered from elbow and shoulder issues that could have hampered his performance, but he also endured two straight years of sub-4.5 K/9 marks! That’s not going to get it done. He then spent the majority of the 2010 season pitching for the Triple-A club.
Fast forward to 2011, and suddenly Perkins is now a full-time reliever. And a damn good one at that. As is usually the case with starter to reliever transitions, Perkins’ fastball velocity jumped and he began featuring a slider as his primary complement to the heater. The slider was fantastic and his SwStk% skyrocketed, bringing his K% along for the journey. His velocity took another step up in 2012 and bumped his strikeout rate again. After closing out game for the Twins during the second half of 2012, he opened 2013 as the de facto closer. His success is just another of many examples illustrating why the idea of needing a proven closer is hogwash.
So when healthy, Perkins has been a top-flight reliever for three years running now. But, he had arthroscopic knee surgery in October and the latest tidbit is that his “(right) knee is rounding into shape”. While the expectation is that he’ll be ready for the start of the regular season, there’s no guarantee.
Jared Burton has acted as the top setup man and racked up seven saves over the past two seasons in Minnesota. He has turned himself into a pretty solid reliever, improving his control and watching as his SwStk% has surged. He has swapped out his cutter for an increased use of his changeup and that change has been awesome, inducing a SwStk% between 19% and 20% over the last two years. He should be the clear favorite to step in for Perkins if need be.
Brian Duensing is the requisite LOOGY and is another failed left-handed starter who transitioned to the bullpen. Though he held righties to a .311 wOBA, which was better than lefties, his xFIP versus the former was a ghastly 5.00, compared to a 2.41 mark against the latter last season. He faced about the same number of batters from each side of the plate, but his splits suggest he shouldn’t be. A tiny 2.6% HR/FB rate versus righties created the illusion that he could be effective against him. Once that regresses, the Twins should realize he is only to be trusted against same-handed batters.
Casey Fien was the breakout star of the Twins bullpen last year, though you wouldn’t know it by just looking at ERA. He posted a nearly 30% K% to go along with pinpoint control, resulting in a strong 2.29 SIERA. The various data providers seem quite confused about what Fien is throwing, but since both the BIS and Brooks Baseball data both agree he’s been primarily throwing a four-seamer and a cutter, I’ll assume that this is the case.
While the classifications from PITCHf/x are probably wrong, we could still marvel at the Swstk% marks of the pitches it thinks he throws. Every single one of them was in the mid-teens! While the SwStk% of the off-speed offerings are potentially sustainable, I can’t imagine he could repeat those marks for his four-seam and two-seam fastballs. Of course, few pitchers in baseball have the skills to sustain an overall 14.2% SwStk% to begin with. So while Fien is sure to regress, he should still see his ERA plummet and earn value in leagues that MRs earn value in.
Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year. He produces player projections using his own forecasting system and is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. Follow Mike on Twitter @MikePodhorzer and contact him via email.