Tumultuous would be but one apt descriptor of Luke Weaver’s 2018 season. Any statistician could cherry pick his numbers and tell you the same; his K/9 fell by nearly three to 7.99, his BB/9 rate was up by over a full walk to 3.56, and his FIP and xFIP reflect that his ERA of 4.95 was perhaps marginally due to bad luck, at best.
Rise Up the Ranks
A former first-round selection by the St. Louis Cardinals in 2014, Weaver was ranked as impressively as the 50th-best overall prospect in baseball at one point in his minor-league career. Though highly touted, Weaver never projected as a strikeout machine: slightly undersized at 6’2”, 170 lbs, – this coming from a writer who stands at a statuesque 5’5” after stretching – the 25-year-old relies primarily on a fastball at about 94 mph, as well as a changeup clocking in the mid-80’s.
Back in 2016, Weaver had his first cup of coffee in the bigs when the Cardinals needed a starter towards the end of the season. It proved to be a mixed bag for Weaver; in his first six starts, he pitched to the tune of a 3.48 ERA with peripherals that reflected that it was no fluke. Unfortunately, whether due to fatigue, hitting adjustments, or a combination of the two, things then began sputtering, leaving him with a 5.70 ERA by year’s end.
Then came 2017, when Weaver began to soar. Accruing seven wins on the year (even though wins are admittedly a terrible statistic), Weaver succeeded to a line of a 3.88 ERA, a 3.17 FIP, a 2.93 xFIP, a 1.26 WHIP, and a phenomenal 10.74 K/9 rate. Sure, there were numbers that likely were outliers in helping Weaver to have such success, – strand rate, ground ball percentage, and swinging strike percentage to name a few – but on the whole, Weaver put together a terrific season that alluded to even greater things to come… or so everyone thought.
2018 proved to be an enormous step back for the young pitcher – indeed, by the end of 2018, the Cardinals had no choice but to demote Weaver to the bullpen. His command seemed to escape him at times, and he struggled to consistently retire left-handed batters in particular, allowing them to hit .291 with an OPS of .841 against him on the season.
As fate would have it, this proved to be Weaver’s swan song in St. Louis; following the season, the Cardinals shipped off Weaver, catcher Carson Kelly, infielder Andy Young, and a competitive balance draft pick to the Arizona Diamondbacks in exchange for perennial all-star first baseman, Paul Goldschmidt. Ultimately, this would prove to open up the door of opportunity for Weaver once again, moving him from a questionable situation in St. Louis to an all-but-guaranteed rotation spot in Arizona.
While his successes over the prior seasons put up a facade to mask Weaver’s weaknesses, one narrative that has continued to follow Weaver throughout his career is that a consistent third pitch has seemingly eluded him. Looking back at 2018, he utilized a curveball as a third pitch 12.7% of the time, but he would be the first to tell you he has yet to master it.
More notably, in an interview with FanGraphs prior to this season, Weaver spoke in-depth about tinkering with a cutter-slider, along with improving his curveball. Interestingly, Weaver notes that he actually had some success with a cutter-slider coming up through the minor leagues, but as can happen with any pitch, Weaver lost a true feel for it and felt uncomfortable trying to force it into major league games. As a result, Weaver explained how he used this off-season as an opportunity to bring this cutter-slider back into his repertoire.
Thus far in 2019, the desert of Arizona has proven to be an oasis for Weaver – and he’s out to prove that this is no mirage. Whether attributable to the change of scenery, extra motivation following the trade, or constantly transforming himself from a two-pitch pitcher to a four-pitch-wielding ace, the numbers speak for themselves; through five stars this season, Weaver has yet to allow more than four runs while producing a sparkling 3.33 ERA, 2.56 FIP, and 3.13 xFIP, along with a rebounding 10.33 K/9 rate. Projected as the number four starter for Arizona prior to the season, if Weaver can continue the progress on his pitching repertoire and keep pitching in line with these numbers, he’ll establish himself as a frontline ace in no time.