Phillies Place Taijuan Walker On 15-Day Injured List

The Phillies announced this morning that they’ve placed right-hander Taijuan Walker on the 15-day injured list due to inflammation in his right index finger. Right-hander Michael Mercado was recalled to the majors in a corresponding move. Mercado’s first appearance will be his big league debut.

Walker, 32 in August, has had a difficult 2024 season as he’s dealt with both injuries and ineffectiveness. A shoulder impingement delayed his season debut until the tail end of April, and he’s struggled considerably in ten starts since then. The righty sports a 5.60 ERA and 5.77 FIP overall on the season, figures that are 37% and 40% worse than the league average respectively. Just two of Walker’s ten appearances have been quality starts, and opponents have batted an eye-popping .278/.353/.511 against him in seven starts dating back to May 16. In other words, Walker’s opponents have teed off in recent weeks to achieve results roughly comparable to those Guardians star Jose Ramirez (.271/.330/.528) has posted this season.

Walker’s struggles came to a head Friday night against the Diamondbacks, when the righty allowed four runs on five hits and three walks across just four innings of work while striking out only three batters. Manager Rob Thomson told reporters (as noted by MLB.com’s Injury Tracker) yesterday that Walker was dealing with a “hot spot” on his finger and suggested that the issue has “been probably going on for a while.” Specifically, Thomson suggested that the injury may have impacted the efficacy of Walker’s splitter. The splitter was Walker’s most commonly used pitch last year, when he threw it 33.2% of the time according to Statcast. That usage has dropped to just 17.4% in 2024, and MLB.com notes that he’s thrown the pitch just sixteen times total over his past two starts.

That drop in usage has corresponded with a drop in efficacy. 2023 saw opposing hitters hit just .205 against Walker’s splitter, with a .295 slugging percentage and a .257 wOBA. Those strong results are a far cry for what the right-hander has produced with the pitch this year, as opponents have hit a whopping .426 with a .704 slugging percentage and a wOBA of .477. That .426 figure is the highest average allowed by Walker on any pitch this year, in sharp contrast to last year where his splitter boasted a lower average against than any pitch in his repertoire except for his rarely-used sweeper.

Given the fact that Walker’s finger issue has seemingly impacted his ability to throw his most important pitch, it’s hardly a surprise that the right-hander has suffered such extreme difficulties to this point in the season. Going forward, the Phillies will sit the righty down for at least the next two weeks in order to give the inflammation time to settle down. It’s surely a fairly easy decision for Philadelphia to not have Walker continue to try and play through the issue given the presence of right-hander Spencer Turnbull. Turnbull has been excellent for the club this year while swinging between the rotation and the bullpen, with a 2.63 ERA and 3.57 FIP in 51 1/3 innings across 16 appearances (six starts).

While Turnbull has not started a game since late April, the righty threw 49 pitches in his most recent outing on Friday and figures to be able to step into the rotation and offer the Phillies solid production in Walker’s stead. That leaves the long relief role out of the bullpen to Mercado, who is set to replace Walker on the club’s roster. Mercado was the Rays’ second-round pick in the 2017 draft but did not make an appearance at the big league level with the club before being traded to the Phillies back in November. Philadelphia swiftly placed Mercado on their 40-man roster and sent him to Triple-A to open the season, where he’s excelled with a 1.71 ERA and a 22.8% strikeout rate in 47 1/3 innings of work split between the rotation and bullpen at the level.