The Minnesota Twins found a left-handed reliever in their stockings on Christmas, as the team announced on Tuesday that Zach Duke had passed his physical and signed a one-year deal with the club.
According to Mike Berardino of the St. Paul Pioneer Press, the deal is worth roughly $2 million with incentive bonuses totaling up to $1.5 million. Paul Lambert of KFAN first had the news of an agreement.
Duke signed a three-year, $15 million deal with the Chicago White Sox prior to the 2015 season, but was traded to the St. Louis Cardinals for outfielder Charlie Tilson on July 21, 2016. Duke underwent Tommy John surgery in October of that year, but managed to return last July — a remarkably fast return, for what it’s worth — to make 27 appearances as a specialist (18.1 innings) for the Cardinals down the stretch with a 3.93 ERA (5.28 FIP).
Duke, who turns 35 on April 19 and is the exact same age — down to the day — as Joe Mauer, came up as a soft-tossing, workhorse lefty in the Pirates system back in the mid-2000s. After that part of his career fizzled, Duke kicked around with the Diamondbacks, Nationals and Reds before he broke through as a reliever in 2014 with the Milwaukee Brewers.
For the three years spanning from 2011-13, Duke worked almost exclusively as a reliever (55 games, 10 starts) and posted a 4.81 ERA, 4.4 K/9 and a WHIP of 1.51. In the four years since, Duke has posted a 2.85 ERA in 253 games (198.2 innings) with 10 K/9 and a WHIP of 1.21.
The strikeout surge is certainly impressive, and he’s right on the cusp of decent with his command over that stretch. He keeps the ball on the ground (50 percent for his career, 57 percent or higher in every year from 2014-16) which, when combined with his usual penchant for strikeouts, can take some of the sting out of the walk rate.
With that said, since he’s been used like a specialist — the easiest way to find these are to compare appearances to innings pitched — that typically means he’s coming in to just face a batter or two, and that’s when walks can be the most harmful.
Nonetheless, when he’s right, he’s a much better gamble than Craig Breslow at this point in their respective careers, but like the lefty the Twins brought in last year, he’s a high-character veteran that’ll only boost morale in the clubhouse.
Cardinals manager Mike Matheny was singing Duke’s praises on MLB Network Radio during the winter meetings. Duke was going through Tommy John recovery concurrently with uber-prospect Alex Reyes, and Matheny said that the veteran lefty was a great mentor since he was a few months ahead in the process, and was able to help the youngster navigate, and more importantly avoid some of the bumps in the recovery road.
Reyes, who turned 23 in August, had his surgery in February just a few months after he was named the No. 1 prospect in baseball by Baseball Prospectus.
Duke’s repertoire doesn’t look too different from his days as a starter, but there are some things to key on. He’s still sitting in the 88-90 mph range with his fastball, but some pitch classifications grapple with what to call his secondary pitches. PITCHf/x says he upped the usage on his slider significantly in 2014 — his breakout year with the Brewers — while the other pitch classification system housed at Fangraphs calls it more of a cutter that comes in a bit firmer (81-83) than his slider (75-76). Brooks Baseball says he went heavier on the sinker — this explains the grounders — and threw more curves and sliders, but almost no cutters.
Duke’s pitch splits at Fangraphs show a good slider whiff rate (routinely 16 percent range) and an excellent one on his curve as well (20-23 percent). His career numbers are crowded by his innings count as a so-so starter, and his 2017 numbers reflect a pitcher returning from significant surgery, like a huge drop in curveball whiff rate (10.8 percent) in a sample size that really isn’t indicative of much (fewer than 500 pitches).
Berardino noted that team doesn’t necessarily view him as a specialist, and that’s an interesting theory.
Here are his wOBA splits versus lefties and righties since his 2014 breakout:
- 2017 – .291/.246
- 2016 – .257/.289
- 2015 – .273/.341
- 2014 – .258/.262
When taken collectively, that’s a .266 wOBA against left-handed hitters and a .296 mark for righties. Since that can be hard to get a strong grasp on, righties have hit .221/.322/.353 on Duke over the last four years, while lefties have hit just .206/.285/.308.
In other words, assuming he’s back to healthy, this is a pretty good gamble. He’s the kind of guy who can head into a game with a left-right-left matchup and be trusted to get through the inning unscathed, assuming he’s throwing strikes. As far as intriguing relief arms available on the market this year — and it’s a really long list — he definitely was a part of that group.
And it’s just a one-year deal, so if he falters it’s extremely easy to cut the cord and move on.
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