PHILADELPHIA -- Bryson Stott’s pinch-hit, two-run home run in the seventh inning Sunday at Citizens Bank Park might not have proved pivotal if Taijuan Walker had not corrected himself since he pitched Wednesday in San Francisco.

Walker could not find the strike zone that afternoon at Oracle Park. He threw 40 pitches. He lasted just two-thirds of an inning.

It stirred further concerns about the Phillies’ rotation, especially with the team moving forward without an obvious No. 5 starter. Walker signed a four-year, $72 million contract in December to provide stability to the rotation behind Zack Wheeler, Aaron Nola and Ranger Suárez. But nine starts into his Phillies career, he had a 6.53 ERA, including a 9.45 ERA over his previous five entering Sunday.

Walker, however, made what he called a “very, very small” fix to his delivery, which allowed him to pound the strike zone Sunday in a 2-1 victory over the Cubs.

“I knew what it was,” Walker said. “I was off just a little bit.”

Walker, starting on short rest for the first time in his career, allowed two hits and three walks and struck out three in 5 1/3 scoreless innings.

It was one of his best starts of the season.

“Honestly, I just wanted to attack the zone today,” Walker said.

Phillies manager Rob Thomson asked Walker in person on Friday if he could pitch on short rest. Philadelphia optioned left-hander Bailey Falter to Triple-A on Tuesday, and Sunday would have been his turn in the rotation. The Phillies, however, hoped to push that vacant spot back to Tuesday.

“I didn’t want to do it by text or by phone,” Thomson said. “I wanted to see his body language when I asked him.”

Walker said yes without hesitation.

“I threw 40 pitches, I felt like I really didn’t do much,” he said. “It was one of those games that I kind of wanted to flush quickly.”

Thomson said Sunday morning that he wanted to see Walker throw more strikes against the Cubs. Walker entered the game throwing first-pitch strikes to only 59.7 percent of the batters he faced this season, which was below league average (60.8 percent) and his lowest mark in a season since 2020 (a career-low 56.9 percent). Walker’s overall strike rate (62.3 percent) was below league average (63.8 percent), too.

But Walker threw first-pitch strikes to 17 of 19 (89.5 percent) batters faced on Sunday, which was the best mark of his career. He threw 55 strikes over 87 pitches (63.2 percent) overall.

It allowed Walker to keep hitters on their heels, work quickly and stay out of trouble.

“Just being aggressive in the zone,” Walker said. “I know I had the three walks, but for the most part everything was in the zone. I got early, quick outs and just made them put the ball in play.”

Seranthony Domínguez, Matt Strahm, Connor Brogdon, Gregory Soto and Craig Kimbrel allowed a combined one hit, one run and three walks and struck out five the rest of the way. The bullpen has a 3.25 ERA in 32 games since April 15. Remove that nightmarish three-game series at Dodger Stadium to open May, and it has a 2.08 ERA since April 15.

Thomson started Josh Harrison at second base with Cubs left-hander Justin Steele on the mound. But with right-hander Adbert Alzolay entering the game in the seventh, he sent Stott to hit.

“Probably every other inning I was taking live BP and flips and stuff like that,” Stott said. “You never know what can happen in a game, when you’re going to go in and whatnot. So I just tried to stay as ready as I could.”

Stott drilled a 1-2 fastball into the seats in right field to give the Phillies a 2-0 lead. It wouldn't have been a game-winner without Walker’s about-face.

“He was going right at them,” Stott said. “Just coming back on three days' rest, it doesn’t matter how many pitches he threw or didn’t throw, I think it says a lot about him and how much he wants to win. That was big for us.”