PHILADELPHIA -- Taijuan Walker's path to signing a four-year deal with the Phillies started a couple weeks ago on a Zoom call with a Philadelphia contingent that included president of baseball operations Dave Dombrowski, manager Rob Thomson and pitching coach Caleb Cotham.

But Walker's journey toward becoming one of the more sought-after pitchers on the free agent market actually started back in May in, of all places, Philadelphia.

It was in the midst of opening his 2022 season with three consecutive starts against the Phillies that Walker decided to try out a new grip on his splitter. It quickly became his best pitch -- and his go-to offering on his way to finishing 12-5 with a 3.49 ERA for the Mets last year.

"I had gotten in some jams and I was getting beat by my fastball -- and I realized how good my splitter was," said Walker, who was introduced by the club on Friday at Citizens Bank Park. "From that day forward, I was just telling myself, 'OK, if I'm going to get beat, I'm going to get beat by my best pitch.' And that's the splitter."

The pitch itself isn't new. Walker has thrown a splitter his entire career, but it's produced mixed results. From 2013-21, he threw his splitter just 16.5 percent of the time. Opponents hit .269 with a .438 slugging percentage against the pitch, which registered a 25.3 percent whiff rate.

In 2022, however, Walker's splitter usage jumped to 27.6 percent -- his second-most-used pitch, behind only his four-seamer (29.5 percent). He held opposing hitters to a .195 average (41-for-210) and a .267 slugging percentage with the splitter.

Walker also used his revamped splitter to finish off 54 strikeouts, making it his most effective putaway pitch. His 29.0 percent whiff rate was also his best with any pitch.

So what changed?

Walker started using Carlos Carrasco's grip. That's right, on a Mets rotation that featured three-time Cy Young winner Max Scherzer and two-time winner Jacob deGrom -- each of whom also taught Walker plenty, he said -- it was instead Carrasco who made perhaps the biggest impact.

After toying with the new grip a bit, Walker decided to try out both versions in his May 5 start against the Phillies.

"His grip just felt more comfortable, and I was just seeing more consistent action with it. So thank you, Cookie, for that," Walker said, referring to Carrasco by his nickname. "But ever since I saw how consistent it was, I've just started throwing it more and seeing the results, so that's been good for me."

It's those results -- and the potential of that splitter -- that made Dombrowski eager to add Walker to a rotation that already features Zack Wheeler, Aaron Nola and Ranger Suárez. As for the final spot in the Phillies' rotation, that figures to be a battle between left-handers Bailey Falter and Cristopher Sánchez, as well as top pitching prospects like righty Andrew Painter.

"When you're trying to win a championship, you need quality starting pitching, as we know," Dombrowski said. "Normally, it's five -- you're really looking for five quality starters. We're just in a situation where we're unique [and] we have some really good young pitchers who are coming. ... All of a sudden, we're in a spot where you can throw out, on an everyday basis, a Wheeler or a Nola or a Walker or a Suárez and then one of those youngsters.”

Walker is excited about the idea of joining that rotation. He's also excited about pitching to J.T. Realmuto, whom Walker called "the best catcher in the game." He's stoked about pitching in front of the "passionate" Philadelphia fan base.

But none of those things are the most exciting part about signing with the reigning National League champions.

"The biggest one is, I don't have to face [Kyle] Schwarber anymore," said a smiling Walker, who has allowed five career homers to Schwarber -- his most to any hitter.

Put it all together -- and toss in the addition of superstar shortstop Trea Turner earlier this offseason -- and Walker knew Philadelphia was the right place for him.

"Just to be added with Nola and Wheeler and Suárez, in that rotation, and I really liked the lineup, one through nine can do damage," Walker said. "I was just really excited about all of that. They were in the World Series last year. Just ready to win. Getting Trea Turner was huge. It was just all exciting things for me."