Sometimes baseball players get it all figured out and go from prospect-with-questions to "holy crap". Just so with Astros' starting pitcher Lance McCullers in 2015, when he blew past Double- and Triple-A to grab a hold of a major league rotation spot and help propel the club to their first playoffs since 2005.
Prior to the season, Fangraphs' Kiley McDaniel--now Assistant Director of Baseball Operations with the Atlanta Braves--had this to say about McCullers:
One scout said he thinks McCullers turns into a #3 starter that throws a shutout one game, then walks five guys the next game. The backup plan is a closer along the lines of Brad Lidge or Francisco Rodriguez, so the Astros should get a solid contributor as long as McCullers stays healthy.
The opinion that McCullers was a two-pitch pitcher who might be best suited in a bullpen ace role was shared universally by internet analysts and scouts, from Baseball America to Baseball Prospectus, to even the Crawfish Boxes. McDaniel's ultimate projection on him was that of a #4 starter or a closer with high risk of bust attached.
One statement in McDaniel's 2014 report card stands out in retrospect:
I saw him a half dozen times in his draft year and noticed that McCullers was making adjustments each time out, smoothing out his delivery, throwing more strikes and integrating a changeup, all against high school competition where none of those things were necessary to get the W. [emphasis mine]
That changeup was the key that eventually took McCullers from interesting but risky prospect to a borderline ace starter in just his rookie season. Jonah Keri at the now-defunct Grantland (sadface) wrote a whole article about McCuller's changeup, and it is fantastic. Go read it now. We'll wait.
Here's the changeup, courtesy of @CespedesBBQ and the Grantland piece (GO READ IT!):
The addition of that changeup, which induced a whiff 31% of the time it was swung on, turned him into a pitcher with an arsenal of three deadly pitches - a fastball that can reach 97 mph, a curve that averages more than 10 mph slower and dies on right-handed batters, and an 88 mph change-up that fades away from left-handers.
McCullers suffered walk woes in the minor leagues, and during a later interview insisted that the walks were a result of development, of working on things he wasn't comfortable with in order to become a better pitcher. It is hard to question his statement now, because walk rates are supposed to get worse for pitchers as they climb the professional ladder and competition gets harder. Bucking that trend, McCullers' progressed from a 13% walk rate in Advanced-A to 11% at AA, and finally to 8% in the majors.
The 2015 results of his development were an 0.56 ERA and 37% strikeout rate at AA that earned him an early promotion to the majors, skipping AAA entirely. In the Majors, he performed at a level that would have earned him Rookie of the Year consideration during any season in which he weren't overshadowed by teammate Carlos Correa. McCullers finished up the season having thrown 126 innings in 22 starts with a 3.22 ERA, striking out more than a batter per inning. He threw one start in the playoffs, pitching 6+ innings and allowing only two earned runs while striking out seven and walking two (2.84 ERA).
In 2016, McCullers will be a mainstay in one of the American League's strongest starting rotations, though manager A.J. Hinch has already announced that the Astros will manage his inning count closely to keep him fresh for an extended playoff run.
Projection systems are expecting a bit of a performance drop in 2016 for McCullers, but not enough to remove him from the ranks of the best pitchers in Major League Baseball. Partially, this drop (3.72 ERA projected by Steamer and 3.64 ERA by ZiPS) is due to algorithms that are including his messy 2014 season at Lancaster, but also predicting negative regression on Batting Average on Balls in Play.
Reasonably, Astros fans can believe that these ERA's represent the high end of true expectations due to the development of his change-up, maintaining his walk rate around 2015 levels, and the presence of an excellent catcher helping him out.
Fearless prediction: 170 IP (not including playoffs), 3.50 ERA, 185 strikeouts, 14 wins.