The Philadelphia Phillies have mapped out their plan for Walker Buehler.
On Sunday, the club added two arms by signing Buehler and claiming reliever Tim Mayza off waivers from the Pirates. Both are postseason-eligible. Mayza has already joined the active roster as part of the September expansion, while Buehler will need a bit more time.

Per Matt Gelb of The Athletic, Buehler agreed to a minor-league deal and will first make a start for Triple-A Lehigh Valley. After that outing, the Phillies intend to call him up and have him debut on Sept. 12 against the Kansas City Royals as part of their rotation.

While there was some uncertainty about whether Philadelphia would use him out of the bullpen, the team views him as a starter. “He’s happy with the plan. We’re happy with the plan. And we’re very excited to have him because we think he makes us better,” said president of baseball operations Dave Dombrowski.

Once Buehler joins, the Phillies will shift to a six-man rotation to help manage workloads, particularly for Cristopher Sánchez and Jesús Luzardo, who are both nearing or surpassing career highs in innings pitched.

Phillies Using Smart Strategy With Walker Buehler’s Addition
There’s a strong possibility Walker Buehler shifts to the bullpen once October arrives. Still, the Phillies want to give him a look as a starter first before committing to such a role change this late in the year—something the Red Sox unsuccessfully tried with him earlier this season.

Philadelphia is confident in pitching coach Caleb Cotham’s track record of unlocking pitchers’ potential, and they believe he can do the same with Buehler, who has struggled to find consistency this year.
“This year hasn’t been as good for him as some other years, but we still like a lot of his stuff. We think we see some things that can hopefully help him. He’s willing to work with us,” president of baseball operations Dave Dombrowski said.
The arrangement appears promising for both sides. Buehler will make a tune-up start in the minors before debuting in mid-September, slotting into a six-man rotation. That strategy eases the workload on lefties Cristopher Sánchez and Jesús Luzardo while giving the club a chance to see how Buehler stacks up alongside Aaron Nola and Taijuan Walker among the right-handers.
At this point in the season, the priority is putting the Phillies in the best position to chase a championship. Even if Buehler isn’t the ultimate difference-maker, taking the chance to see if he can be is a much better play than not trying at all.