Can Anyone Fix Walker Buehler? Anyone?

Aside from a brief run last October — one that culminated with a surprise cameo to close out last year’s World Series — Walker Buehler has scarcely resembled the pitcher who from 2019–21 made two All-Star teams and helped the Dodgers win a championship. The Red Sox took a shot at fixing him, and now the Phillies will try as well, hoping at the very least that he can provide some useful innings down the stretch and land a spot on their playoff roster.

The 31-year-old Buehler, who signed a one-year, $21.05 million deal with Boston in January, was roughed up for a 5.45 ERA and 5.89 FIP in 112.1 innings with the Red Sox, slightly higher than his marks with the Dodgers last year (5.38 ERA, 5.54 FIP in 75.1 innings) after returning from his second Tommy John surgery. He made 22 starts for the Red Sox, but his continued struggles led the team to pull him from the rotation after his August 19 start, a four-inning, four-walk, two-run outing against the Orioles. After just one relief appearance, in which he allowed two runs in 2.1 innings against the Yankees on August 24, the Red Sox released him last Friday while still owing him roughly $3.4 million.

The Red Sox — who at 77-62 are tied for the AL Wild Card lead despite weathering numerous starting pitcher injuries and disappointments — had considered replacing Buehler in the rotation with rookie Richard Fitts. But when the 25-year-old rookie landed on the injured list due to a bout of neuritis in his right arm, the team needed to add another starter, and the call-up of prospect Payton Tolle cost Buehler his spot on the 40-man roster.

“[Our] hope and our expectation was, we were going to be able to provide enough runway to give [Buehler] a chance to settle in and transition into that role and then contribute down the stretch in getting some meaningful outs for us,” said Red Sox chief baseball officer Craig Breslow on Friday. “But circumstances changed, and we had [an injury with Richard] Fitts and losing that length piece in the ‘pen and needing a starter tonight, it just felt like this was what was best for the team at this point.”

Thanks to the looming deadline for playoff eligibility — a player must be on a team’s 40-man roster or 60-day injured list by noon ET on September 1 in order to participate in the postseason — Buehler didn’t stay a free agent for long. On Sunday, the Phillies signed him to a minor league contract; they’ll pay him only the prorated minimum salary, and the plan is that he’ll make one tune-up start with Triple-A Lehigh Valley before being recalled.

Which isn’t to say Buehler will necessarily be starting for the Phillies in October, but they suddenly have an opening. When Aaron Nola came off the injured list on August 17 after a three-month absence due to a right ankle sprain, the Phillies planned to include him in a six-man rotation along with Zack Wheeler, Cristopher Sánchez, Ranger Suárez, Jesús Luzardo, and Taijuan Walker. Unfortunately, just as Nola was activated, Wheeler was discovered to have a blood clot near his right shoulder, and last week the Phillies learned he would miss the remainder of this season and the start of the next due to surgery — the removal of a rib — to alleviate venous thoracic outlet syndrome.

While the loss of Wheeler — who, in addition to his perennial Cy Young contention, has been one of the game’s best in the postseason in recent years — is a major blow, Sánchez (2.65 ERA, 2.59 FIP), Suárez (3.02 ERA, 3.05 FIP) and Luzardo (4.05 ERA, 3.02 FIP) are easy choices to be part of the Phillies’ postseason rotation. The fourth slot, however, is up for grabs, and Nola (6.47 ERA, 5.04 FIP) has not pitched well enough in his return to convince anyone he’s a strong choice. Walker, who has pitched to a 3.92 ERA and 4.88 FIP in 105.2 innings as a swingman, is probably the leading candidate for the fourth spot. He turned in solid results in August (3.14 ERA, 3.23 FIP in 28.2 innings), though those numbers are padded by two starts against the Nationals and one against the Orioles. His last two starts have come against contenders, first the Mets on August 27 and then the Brewers on Sunday; those two teams combined for 17 hits and nine runs against him in nine innings.

With top prospect Andrew Painter, a 22-year-old righty, pitching to a 5.36 ERA and 4.92 FIP at Lehigh Valley (and at some point facing an innings cap), the Phillies decided to look outside the organization, and a couple things worked in Buehler’s favor beyond his minimal cost. For one, the Phillies got a good look at him when he pitched well against them on July 21; he allowed two runs (one earned) on six hits and one walk while striking out four over seven innings, matching his longest start of the season. For another, when the team had a video conference with Buehler, the pitcher hit it off with Phillies pitching coach Caleb Cotham, a fellow Vanderbilt alum.

“This year hasn’t been as good for him as some other years, but we still like a lot of his stuff,” said president of baseball operations Dave Dombrowski on Sunday. “We think we see some things that can hopefully help him. He’s willing to work with us.”

With Sánchez and Luzardo both on pace to set new career highs in innings, giving them a couple extra days off in September isn’t a bad idea, and there’s no harm in adding Buehler to the rotation competition. Performance-wise, there’s nowhere to go but up. Buehler’s 16.5% strikeout rate and 10.8% walk rates are both career worsts, a step below last year’s 18.6% strikeout rate and 8.1% walk rate… and several steps down from his peak, to say the least:

Oof. Mind the gap there; the dotted lines cover for the fact that Buehler went 23 months — from June 2022 to May ’24 — without appearing in a major league game. He didn’t get Tommy John surgery until August 23, 2022, and despite it being his second (his first was in August 2015, just after the Dodgers drafted him with the knowledge he would need the procedure), he made a rehab appearance for Triple-A Oklahoma City on September 3, 2023. The Dodgers even flirted with the possibility of bringing him to the majors that month before coming to their senses, but given that most pitchers undergoing a second TJ take 15 months or more to return to the majors, it’s fair to wonder if that early ramp-up contributed to Buehler’s decline.

While Buehler’s average four-seam fastball didn’t lose much velocity from 2022 (95.2 mph) to ’24 (95.0), it had already receded from a peak of 96.8 mph in ’20. He’s now down to an average of 94.0 mph, and his arm angle has dropped from a high of 51 degrees in 2021 to 46 in ’22 and ’24 to 43 degrees this year. Even as he’s remixed his arsenal in response to his waning four-seamer — emphasizing his sinker, cutter, and slider — the pitch modeling systems aren’t buying what he’s selling:

Even last year, both PitchingBot and Stuff+ viewed Buehler’s combination of stuff and location/command as workable enough to be average or better. By both measures, the stuff has fallen off and the location/command is even worse. Stuff+ still grades Buehler’s slider (including a sweeper) and knuckle curve as above-average pitches, but PitchingBot doesn’t see any of them as quite average (50 on the 20–80 scouting scale).

As you can see, Bueheler’s throwing a lot of different pitches. He mixes them differently based on batter handendess, throwing nearly as many sinkers as four-seamers to righties along with his slider, sweeper, and cutter. He throws the sinker much less to lefties, and uses the knuckle curve almost exclusively against lefties:

The problem is that while his mix is generally working against righties, it’s not working against lefties:

Buehler’s overall platoon split (.329 wOBA allowed against righties, .384 against lefties) only hints at his problems. Righties are beating the tar out of his increasingly pedestrian four-seamer and his suddenly ineffective cutter, but even so, his sinker, slider, and sweeper have been very effective against them, with the two breaking pitches generating high whiff rates. By contrast, he doesn’t have anything that’s working well against lefties anymore unless you want to grant him some leeway for the gap between the actual and expected results on his changeup, a pitch he throws just 11.2% of the time to them. Last year, the knuckle curve at least produced a 29.4% whiff rate against lefties while holding them to a .311 wOBA, while the cutter held them to a .264 wOBA.

Some of Buehler’s ineffectiveness owes to his declining command and poor location. Here’s a look at the zone percentages and wOBAs allowed against his four-seamer while facing righties:

As you can see, over the course of those seasons, Buehler’s whiff rates have declined and opposing batters’ slash stats have improved. Look more closely and you can also see, for example, that in 2022, 7.6% of Buehler’s four-seamers ended up in the middle of the plate (Gameday zone 5) and batters produced a .414 wOBA against them; they went 1-for-5 with a homer against the 12 four-seamers that wound up there. In 2024, while so much else was going wrong, that middle-middle percentage dropped to 4.3% and that wOBA to .000, as righties went 0-for-3 against the six four-seamers that wound up there. This year, 12.9% of Buehler’s four-seamers to righties have ended up middle-middle and they’ve pounded it for a 1.004 wOBA, going 5-for-9 with four homers against those 26 pitches. Mercy.

Given how many different pitches Buehler throws, we could fill up a whole article with such comparisons, but these graphs generally tell variants of the same story. Here’s a look at Buehler’s zone percentages and wOBAs allowed against his knuckle curve while facing lefties:

The big take-home here is what’s outside the zone, particularly in the lower half: the shading has gone from various pale blues to pinks as lefties have stopped chasing the pitch when it’s below the strike zone, causing Buehler’s whiff rates to drop about 10 percentage points while his wOBA against has nearly doubled from 2022 to ’25. What was once a strength has turned into a liability.

Right now, the numbers don’t give a lot of reasons for optimism about Buehler. Still, just 11 months ago he rebounded from a gut-wrenching regular season and a six-run second inning in Game 3 of the Division Series against San Diego to string together 13 scoreless innings against the Padres, Mets, and Yankees and carve a spot in October lore with his dramatic, unexpected role closing out the World Series. I wouldn’t count on lighting striking twice, but there’s a lot of room between securing the final three outs of a season and providing serviceable innings along the way, and within that broad expanse, perhaps Buehler and the Phillies can find a niche for him to help.