Astros' Collin McHugh is one of the best in the biz

Astros starting pitcher Collin McHugh is one of the most underrated starting pitchers in baseball, and certainly among Astros fans at present.  His name constantly surfaces in internet trade suggestions -- most recently in a fictional trade with the New York Yankees that would net star reliever Andrew Miller in return.  Note that no in-the-know media outlet with ties to any MLB club has bandied about McHugh's name in connection to off-season trades.  But his removal from the Astros' roster in favor of some other player is suggested often enough here at TCB and on other prominent blogs and message boards, that it's worthwhile to examine his performance and what makes him a lot better than fans seem to think.

Overall, the perception is that McHugh experienced a "Down year" in 2015, despite finishing 8th in the AL Cy Young voting this season, ahead of Miller and last year's AL Cy Young winner Corey Kluber.  Quite possibly, the votes came from those archaic holdouts that still have a firm belief that earned wins for a pitcher are a decent gauge of performance, and that McHugh's 19 wins (2nd-most in the AL) earned him consideration.

The "down year" perception is due to a couple factors.  First, his 3.89 season ERA was over a full run higher than his 2014 breakout season in which he allowed only 2.73 earned runs per nine.  This is in large part due to craptastic results in May and June (5.08 and 4.97 ERA) that can be attributed to some loss of command due to a lingering blister on his pitching hand.  Fans remember prolonged struggles, particularly by players that don't have a long track record of success.  And fans have memories of past Astros pitchers who fizzled after one hot year, such as Lucas Harrell from 2012 to 2013.  Unfortunately, impressions of McHugh lingered from his mid-season struggles, and those two months heavily affected his overall season run prevention numbers.

But after the All-Star break, with McHugh presumably healed from the nagging hand injury, he pitched 90 innings of shut-down baseball, earning a 3.11 ERA for the final months of the season.  His 2nd half was more reminiscent of 2014, and should have re-inspired confidence in the fans.  But largely, in the shadow of teammate and AL Cy Young winner Dallas Keuchel, not to mention the dynamic emergence of rookie starter Lance McCullers, McHugh's performance went unremarked by fans, blogs, and the media.

By the numbers

And so the Astros have, in Collin McHugh, a cost controlled starting pitcher who can claim the following after two years pitching for Houston:

All stats are among qualified starters (a sample of 72) from 2014 to 2015.

• McHugh ranks 21st in WAR
• ranks 25th in FIP
• ranks 30th in xFIP
• ranks 32nd in ERA
• ranks 29th in K/9
• ranks 33rd in BB/9

Summarizing, there are between five and ten major league baseball teams for whom McHugh would be the best pitcher on their staff.

So why the skepticism?

McHugh reached the majors as an unheralded almost-non-prospect with the Mets in 2012.  He was traded to the Rockies in 2013.  In both occasions, he failed spectacularly in short stints in the majors and there is not one metric that can be pointed at to argue away his badness.  The Astros, who had reportedly tried to acquire McHugh in trade from the Mets earlier, swooped him up after he was DFA'd by the Rockies.

So based on track record before his acquisition by the Astros, many fans seem to expect that McHugh will turn back into a pumpkin, and that the Astros would be "selling high" by trading him now.  Those fans expect that we've already seen the best McHugh has to offer in 2014.  And they might be right about that, since his 2014 was so incredible.

But there are observable reasons for why McHugh is as good as he is now, and for why he wasn't as good with the Mets and Rockies.

Why he's really good...

Judging by Fangraph's Pitch f/x Pitch Values, Collin McHugh has two well-above-average pitches.  Unlike a lot of starters though, his best pitches are both breaking balls.  He boasts an elite curveball with almost eight inches of drop and some side run that is generated by a massive amount of ball spin (reportedly the reason why the Astros targeted acquiring him).  He also has an un-classifiable slider/cutter that comes in at the same velocity as his fastball but breaks in the opposite horizontal direction by about the same amount.  By "pitching runs above average, per 100 pitches", his curveball has been worth over one run per 100 pitches more than the average ML curveball.  That's...really stinking good.  In fact, it's 9th best in baseball, equivalent to NL Cy Young winner Jake Arrieta's curveball.  McHugh's slider is worth 0.66 runs above the average ML slider, after scoring a ridiculous 2.33 in 2014 and regressing some in 2015.

But the Mets and Rockies didn't know this.  Those clubs were trying to coax McHugh into inducing ground balls by leading with his 2-seam and 4-seam fastballs.  From 2012 to 2013, McHugh threw almost 60% fastballs, 10% of which were 2-seamers intended to induce grounders from opposing batters.  In 2012, he only utilized his slider/cutter 9% of the time.

The Astros said, "To heck with that!"  They instructed McHugh to ditch his 2-seam fastball entirely (he's only thrown it 1% of the time in the past two seasons, and those are probably mis-classifications by Pitch-F/X).  And now he lives off his breaking pitches.

This is an important point.  Where he threw 60% fastballs during his first two (lousy) MLB seasons, during his successful seasons, he threw 60% breaking pitches and eliminated his 2-seamer altogether.  This isn't a tweak in mechanics, and it isn't magical pitch sequencing or pitch framing (though those help).  This is a 100% change in approach designed to maximize McHugh's abilities.

This allowed McHugh to do what other pitchers do - use his best pitches to set up and improve his secondary pitches.  As stated above, most pitchers use their fastball to set up their breaking pitches, because the fastball is their most reliable and/or best pitch.  Keuchel is an example of this, as his elite sinking fastball sets up his breaking pitches to generate more whiffs.  Batters are looking for the sinker, and so are unprepared to deal with a well-executed slurve.

But McHugh appears to be doing the opposite.  He 'boasts' a 91-mph fastball.  it doesn't feature a ton of break, though it does have some horizontal run.  The fastball, on it's own, isn't a very fearsome pitch to a major league hitter.  But his breaking pitches are. And so he makes sure that the batters are looking for that curve and slider/cutter by throwing them most often.  Then, he makes his fastball appear like his breakers, and batters are unable to adjust until it's too late.  This creates a nice number of whiffs on that 'pedestrian' fastball that he would never have gotten in 2012 or 2013.  Take a look at his whiff chart:

McHugh generates whiffs in two extreme locations.  The whiffs at the bottom of the graph are generated by his knee-buckling curveball.  The ones at the top are generated by his "pedestrian 91 mph" fastball.  Because the curveball is thrown with a high trajectory that breaks downward, a fastball thrown high in the zone will look like the curveball until a point in its flight path where the curveball would otherwise break.  The batter, who is looking for the breaking pitches, under-swings the fastball, generating the whiff.

Conclusion

It's evident from pitch selection numbers and the whiff rates generated that McHugh has a vastly different approach than what was required of him as a member of the Mets or Rockies.  From this perspective alone, he cannot be judged based on his results during 2012-2013; he is a different pitcher now.  His results as a Houstonian are excellent and sustainable - even during 2015's "down year" he managed a 3.58 FIP that was 31st-best in the major leagues.  He did this despite an elevated BABIP of .310 (compare to career .299 BABIP) and a lingering blister on his pitching hand.

Collin McHugh is one of the best and most consistently reliable starting pitchers on planet Earth.  There are few, if any, examples in recent history of a contending team trading away a cost-controlled pitcher of his caliber for any return, much less an expensive and older reliever who manages only 60 innings pitched per season.