/cdn.vox-cdn.com/uploads/chorus_image/image/56116061/Untitled_1.1502248253.jpg)
If you haven't noticed from pre-game stories or general usage, there's a new pitch going around the Astros clubhouse. Houston has been known as a club that identifies and targets similar trends in pitchers on their roster, or pitchers they might acquire (as many teams probably do) - it even garnered this Hardball Times story from April 2016 that asked if the Astros starters were too similar, based on low-90s fastball velocity (mind that Lance McCullers, the hardest throwing Astros starter, was out for this period of time).
The story above concluded that many other factors contributed to that poor first month of 2016 from the Astros rotation - and velocity wasn't the main cause. "Similarly, off-speed and breaking pitches play large roles, as well", wrote author Ryan Pollack. The Astros have not kept it secret that they like pitchers with heavy sinker usage and high spin rates - the subject of this post, Colin McHugh, was first signed because of impressive spin rates in his curveball. But in 2017, the pitch l'année is another secondary that's made it's way through the Astros clubhouse.
After coming back from his shoulder injury, Collin McHugh showed up in the Astros rotation last month and started throwing a slider. This is significant, because McHugh's go-to secondary offering, his curveball, is essentially the pitch that got him an early-season "tryout" and an eventual role in the Houston rotation back in 2014. McHugh's 12-6 offering with that impressive spin rate solidified him as a quality mid-rotation starter who could be even better than that at times. (production cost the Astros exactly nothing). Here's what McHugh's usage rate between those two secondary pitches has looked like since the middle of 2016.
:no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/9000869/Brooksbaseball_Chart_4.png)
McHugh's version of the slider has changed hands through the Astros clubhouse more often than Octavio Dotel changed teams - but we can ultimately trace it back to Luke Gregerson's slider of death, thanks to some sleuthing from the Chronicle's Jake Kaplan - McHugh picked it up from Brad Peacock, who picked it up from Jordan Jankowski, who himself picked it up from Gregerson.
If you check the above chart closely, you'll see that McHugh may not have initially picked up the slider this year at all - he started throwing it for really the first time heavily in in game #161 against Los Angeles last October. If you're like me, you probably blocked out the last few meaningless games of last year's disappointing campaign, and didn't notice McHugh's 7.2 shutout innings that night or anything about them. Though it looks like McHugh started throwing the slider then, it's still possible that he kept working on it with Peacock's help during his nearly-four months on the shelf.
In that garbage time game against the Angels, McHugh not only threw the slider more (not quite at the expense of his curveball - we'll get to that later), but generated a significant number of whiffs on it as well.
:no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/9000883/Brooksbaseball_Chart_5.png)
The results from McHugh's slider have been quite encouraging so far. He's throwing the pitch at around 80 mph, a good five mph faster than his slow curve and generating whiffs on nearly 22% of his sliders so far in 2017, not far off from his career whiff rates with the curve.
This article from Jake Kaplan at The Chron says McHugh picked up the slider to attack right-handed hitters, and the heatmaps back that up.
:no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/9003677/McHugh_sl.png)
So far, that's an encouraging whiff rate and conservative location of a new pitch from McHugh - keeping an offering he's probably still trying to get comfortable with away from hitters, and only throwing it to righties in the first place seems a safe route to go. Fangraphs even likes the slider enough to give it a positive pitch value of 2.0 (runs better than average) and 3.58 runs above average per 100 sliders thrown through his first three starts. So even a pitch that McHugh is being "careful" with is showing some really positive results (whiffs and pretty much no hard contact) in a small sample.
Here's the slider in action against Tampa Bay last week on a 1-2 pitch to Wilson Ramos.
That thing has some pretty wicked movement for a pitch McHugh supposedly just started throwing - we're so used to seeing the low to mid-70s, looping curve from McHugh that this almost looks unnatural for him, but he certainly looks to have some confidence in it.
What about the indirect implications of this new pitch? It probably wouldn't be a good thing for McHugh to cannibalize his curve with the slider. The curve is sort of McHugh's "narrative" pitch - it's what turned him from a low-K, 8.00 ERA pitcher in Colorado and New York into a guy who's averaged a 114 ERA+ across four seasons in Houston. It has appeal because it made McHugh who he is now, and it works - the strikeout rates, spin rates and general consistency of his results throwing off that pitch back up who he's been since 2014.
Fortunately, the curve probably isn't going anywhere. McHugh's early tendency to throw the slider almost exclusively to righties makes it more of a third, conditional option, and A.J. Hinch has limited McHugh's workload in his three starts (he's averaged 86 pitches since coming off the DL, an understandably cautious amount), which skew his curveball percentages down relative to raw counts. Once McHugh gets back to a normal ~100 pitch outing, it's likely we'll see his curveball usage rate rise back to career norms with more chances to throw his best pitch.
It's only fitting that a guy who experienced a career renaissance in 2014 by throwing his nastiest breaking pitch more than a quarter of the time is learning something from Brad Peacock, who's currently following the same path as McHugh - this might be the Year of the Slider in Houston, as Peacock has thrown it at career-high levels with his own unprecedented success. Early returns show that this slider can be a valuable weapon for McHugh - maybe not quite at Peacock levels, but using it ahead in counts, out of the zone and as a differentiator to his other stuff might be all he needs to make it a valuable pitch going forward. Look for McHugh's slider in those scenarios, and let's hope we see more like that 1-2 pitch to Ramos a few more times this season.