It takes incredible talent just to be a fringe major leaguer, and even more talent to be a first-round draft pick and a top 10 prospect, as Lucas Giolito was earlier in this decade. Yet last year, the 6-foot-6 righty was The Worst, at least among the 57 pitchers who threw enough innings (162) to qualify for the ERA title. While good health and the White Sox’s commitment to rebuilding allowed him to take the ball 32 times and throw 173.1 innings, Giolito finished his age-23 season with the highest ERA (6.13) and FIP (5.56), and the lowest strikeout-walk differential (4.5%) and WAR (-0.1), of any qualifier. Ouch.
This year, it’s been an entirely different story, as Giolito has pitched like an ace, posting a 3.20 ERA and 3.30 FIP in 157.1 innings en route to 4.7 WAR, good for fourth in the league. When I set out to adapt my “Most Improved Position Players” methodology to starting pitchers, I strongly suspected that the now-25-year-old righty would come out on top, just as Cody Bellinger did in that exercise. He not only did, he was the runaway winner, scoring points in eight of the nine categories I chose to measure. In three of them, he had the largest improvement of any pitcher, and in four others, he ranked among the majors’ top four.
For those unacquainted with my previous foray, its basis is our handy but somewhat obscure Season Stat Grid, introduced just over a year ago. The grid allows the user to view up to 11 years worth of data in a single category, and to track and rank year-to-year totals and changes based on thresholds of plate appearances and innings. Echoing what I did for the position players, and some of the feedback I received (thankfully no tar or feathers), I chose nine statistical categories where we might look for significant, skill-driven changes. To qualify, pitchers needed to have thrown just 80 innings last year, and 120 this year; for the position players, I used 400 plate appearances last year and 300 this year, but in retrospect realized that some very improved players, such as Christian Vázquez, had slipped through the cracks. With pitchers such as the Yankees’ Domingo Germán (who didn’t even crack my top 20) in mind, time I loosened the pitcher thresholds a bit. For the top 20 pitchers whose changes went in the right direction (lower ERA, FIP, walk and home run rates on the one hand, higher WAR and strikeout, first-pitch strike, groundball, and chase rates on the other), I awarded 20 points for first place, 19 for second, and so on. I went 30 deep on the position players, but found that among the pitchers, often the 25th- or 30th “best” change might be a negligible improvement or even a step in the wrong direction. Read the rest of this entry »