Last year, Trevor Rogers, an unheralded reliever for the Minnesota Twins, had one of the best sliders in all of baseball. In plate appearances ending with the pitch, he struck out 29.5 percent of hitters, walking none. His .165 xwOBA against on it ranked in the top eight percent of baseball. Against convential wisdom though, he only threw it 13.1 percent of the time, relying on his sinker and slider more often. Only one pitcher last year had a lower xwOBA and usage percentage on their slider than Rogers (Tyler Glasnow).
Rogers still managed to put up a serviceable season as the Twins setup man though. His 2.63 ERA and 2.39 FIP were both career bests and his 1.9 fWAR ranked 10th among qualified relievers.
Rogers has taken another step into dominance in 2019. His seen increases in his fastball velocity, strikeout-rate, and soft-hit rate, while seeing his hard-hit rate take a plunge. His ERA and FIP currently stand at 1.98 and 2.68, respectively. It looks better when you single out his last eight appearances, as across 8 2⁄3 innings he’s pitched to a 2.08 ERA and 1.16 FIP, while striking out a whopping 39 percent of the batters he’s faced. He’s one of the hottest relievers in baseball at this current moment.
Perhaps a lot of this can be traced back to that slider I just mentioned. After using it 13.1 percent of the time last season, there’s been an insane jump in its usage this season so far, as it currently stands at 50.2 percent. His increase in slider usage (up 42.5 percent) is by far tops in baseball, with the next closest being Matt Strahm at 23.2 percent. The difference in change in usage is greater from first to second place among 239 qualified pitchers than second to 60th. His season-to-season change makes him an outlier.
Biggest increases in slider percentage from 2018 to 2019
|Rank||Name||Change in SL%|
|Rank||Name||Change in SL%|
This can perhaps be the reason to his strikeout surge. Looking at just two-strike counts, Rogers ranked 308th out of 486 relievers in slider percentage, minimum 50 pitches thrown. This season, he ranks 49th out of 391 pitchers, minimum 10 pitches thrown.
How he garners success of his slider is interesting too. The league-average called strike percentage for sliders is 14.9 percent. Rogers is way above that, as his 22.9 percent ranks third out of 87 pitchers with at least 100 sliders thrown this season, only trailing Jose Leclerc and Noah Syndergaard.
The reasoning behind this could in fact have to do with his release point on his slider. By standards for left-handed pitchers, both his vertical and horizontal release point aren’t what you would call normal, as he ranks in the bottom fifth of baseball for both.
Combine this tough angle for hitters with superb command and you’ll get a lot of called strikes, something that has played a big role in the success for Rogers this season.
Since the beginning of last year, Taylor Rogers, on the account of most metrics, has been one of the more valuable relievers in baseball. And he’s probably not getting the recognition he deserves for it. But housing traits of a dominant reliever, while playing a major bullpen role for a legitimate playoff contender could (and should) get him more credit.