Dallas Keuchel unceremoniously made his major league debut against the Rangers at Arlington on June 17, 2012 for an Astros squad en route to a cringeworthy 55-107 record during their last season as a member of the National League. To be honest, there wasn’t much, if any, excitement behind the southpaw’s debut. Sure, he was a sleeper in some circles, but the left-hander from the University of Arkansas wasn’t exactly viewed as someone who could potentially lead a major league pitching staff in a few years. But the rebuilding Astros afforded Keuchel something that not many teams could at the time: An abundance of opportunity and playing time; a perfect storm for a rebuilding club looking to find a few diamonds in the rough.
Although his performance in the 2012-13 seasons failed to inspire much confidence (5.20 ERA, 4.78 FIP), the left-hander continued to receive work, which led to a grand total of thirty-eight starts. Thanks to the Astros being so dreadful those two seasons — by golly, were they horrid — there wasn’t much of a reason to not give Keuchel ample opportunities to figure it out. At that point, what exactly did the team have to lose? Their place in the standings or postseason aspirations?
However, velocity was never exactly a strong suit of Keuchel, even harkening back to his college days at Arkansas. If he was going to succeed in the major leagues, he would have to generate outs through contact. Without fine control, his upside was viewed as limited in the majors. The early results reinforced those doubts. When compared to his major league contemporaries at the time in 2012, with at least 70 innings pitched, Keuchel had the fifth-lowest strikeout rate at 10.1 percent. His 10.3 percent walk rate that season was even more dismal. He was actually one of three starters with a negative strikeout-to-walk ratio. Outside of his 52.1 percent groundball rate, the numbers weren’t exactly encouraging when analyzing Keuchel from up close or afar.
That said, something started to click on the mound for Keuchel in 2013. For one, there was a spike in strikeouts – up to 18 percent – which justified some attention. His groundball rate also rose higher to 55.8 percent. Even the walk rate saw a decrease to 7.6 percent on the season. In spite of a 5.15 ERA, Keuchel’s peripherals — 4.25 FIP, for example — saw a fair amount of improvement compared to the previous season. The overall numbers still weren’t great, but progress was made. And, yes, some of that improvement is linked to an increase in velocity, even if it wasn’t overly drastic. On a monthly scale Keuchel’s average four-seam velocity between the two seasons improved by one to one-and-a-half miles per hour on the average. Even a slight uptick in velocity can mean the world to pitchers who already have a smaller margin of error than, say, Chris Sale or Noah Syndergaard.
But notice the fifth line highlighted in red? It represents a pitch not previously in Keuchel’s repertoire: a slider. The pitch was arguably the missing piece to the bearded southpaw’s game and something he decided to introduce in 2013 with varying levels of success in subsequent seasons.
Keuchel would then continue to fine tune his method of attack against hitters throughout the next couple of seasons (2014-15), which are arguably the best of his career up to this point in time. He would eventually drop the curveball from his arsenal as he started to emphasize the usage of both his sinker and slider, which accounted for nearly seventy percent of his pitch usage in 2015.
The slider especially added another dimension to how he could approach the opposition, both left- and right-handed hitters. Thrown in the bottom quadrants of the strike zone, a slider breaking away for left-handed hitters or coming in against a right-handed hitter is a valuable out pitch. By utilizing that movement, Keuchel could generate more swing-and-misses without needing a lot of extra velocity.
Here’s a slider beautifully breaking away from left-handed hitter Mitch Moreland back in 2013.
And here’s another except it came in against the right-handed Adrian Beltre in 2015, the season in which Keuchel won his Cy Young award.
By subtly increasing his velocity and focusing on the movement of his pitches into the lower portions of the zone, Keuchel reinvented himself into a top of rotation arm for a couple of seasons. The 2014-15 seasons were his best as he posted a combined 2.69 ERA/3.05 FIP in 432 innings, which would help lead the Astros back to contention. His peripherals also continued to improve as his strikeout rate reached 21.1 percent and his walk rate settled at 5.8 percent across those two seasons. Combined with a league-leading 62.6 percent groundball rate, Keuchel turned himself from a pitcher trying to make it on to a rebuilding club to one of the top pitchers in baseball for a time. It brought validation to what Keuchel was trying to accomplish without the high velocity readings that were becoming the rage in baseball.
Unfortunately, injuries and regression would take its toll on Keuchel as his time with the Astros would eventually reach its conclusion in 2018. The 2016 season, in particular, saw his velocity begin to wane in addition to injuries. A Hardball Times article by Jon Roegele in also illustrates how the strike zone size below the 21 sq. inches mark shrank slightly in 2016 (45” sq. inches) as compared to 2015 (50” sq. inches), which could, in theory, impact Keuchel’s performance more so than other pitchers. It shrank further in 2017 when the strike zone contracted to 42” sq. inches. The former Astro was at his best when the borderline calls at the bottom of the zone go his way, which helped set up chase pitches like his slider. But with a smaller strike zone in tow, Keuchel hasn’t been able to locate his slider like he did and, in turn, appears to have affected his chase rates.
When forced to throw his best two pitches — the sinker and slider — higher in the zone, it is understandable to see both offerings suffer in terms of results. Throw in injuries and a slight decline in velocity, that margin of error for Keuchel largely evaporates.
Sinker and Slider wOBA by Season
The Astros would let Keuchel walk in free agency following their 2018 ALCS defeat by the hands of the Red Sox. Following a brief stop with the Braves last year, the bearded southpaw figures to bring a veteran influence to a young White Sox roster in 2020. Well, if there is a season. Although his absolute peak was relatively short-lived, he still contributed 18 wins above replacement as a starter, which is good for tenth place in club history. For a pitcher who didn’t possess overwhelming stuff, it was delight to see his approach bear good fruit. Not bad at all for a guy without much fanfare when he was first promoted to the majors on that hot summer day in June 2012.