PHILADELPHIA — There’s an irony to the ebb and flow of the Phillies bullpen if you only zoom out far enough to see it.

Relief pitching was, for so many years, the limiting factor on the Phillies’ playoff aspirations, even once they had begun to collect all-stars like J.T. Realmuto and Bryce Harper.

In 2022, with the shape-shifting Ranger Suarez and a revitalized Zach Eflin, they figured it out until they didn’t: Four different players recording postseason saves until Yordan Alvarez caught up to Jose Alvarado in Houston.

Taking a cue from those shortcomings, the Phillies went out to get All-Stars Craig Kimbrel and Gregory Soto, then watched them, respectively, implode and become a non-factor by October 2023.

Lesson learned. So the 2024 Phillies would develop talent internally, nurture a pair of shrewd acquisitions into All-Stars, augment it with one of the game’s most fearsome lefties and then add an All-Star closer at the deadline.

The result? Matt Strahm was bad in the playoffs. Alvarado was worse. Jeff Hoffman was unrecognizable. And Carlos Estevez shut the door in exactly the opposite way he was hired to.

None of that directly impacts how the Phillies have built their bullpen in 2025, but then it can’t help but exert some influence.

The Phillies overinvested in the bullpen in 2024 only to see that unit betray them in the exact moments they were built for. The pendulum swung the other way this winter.

Estevez and Hoffman reaped their riches elsewhere. Jordan Romano and Joe Ross masqueraded as significant additions. Don’t worry about Strahm’s fading velocity or the book being out on Orion Kerkering, or the need to grab Carlos Hernandez off the scrap heap just before the season started.

And so a bullpen that was one right-handed arm short before Alvarado got popped for performance-enhancing drugs feels even more distant from its final form on June 1 than April 1, reason for concern no matter what the standings say.

All that is too much to foist onto the shoulders of Taijuan Walker, who will move to the bullpen effective Sunday, duration unknown.

Manager Rob Thomson doesn’t want to keep yo-yoing the longtime starter on the fringes of the rotation. So Walker will head to the ‘pen with an eye toward condensing his 217 career major league starts into a form amendable to getting three outs three times a week.

“I want to see him in a one-inning stint and see what he can do,” Thomson said Sunday.

The Phillies have a glut of starting pitching and a dearth of relief.

Mick Abel will fill Walker’s starting spot Thursday in Toronto. The Phillies have four capable starters, plus the injured Aaron Nola, plus Abel, plus Andrew Painter once July arrives. That leaves no room for Walker.

The best way to convert starting depth into relief help is via trade, but it’s a one-way door. Abel may be too enticing for that, and Painter’s value as a top prospect coming off Tommy John makes the Phillies reticent to alter his role.

So, Walker will at least have the first chance at owning a bigger role.

“He’s a pro. He really is,” Thomson said. “I’m sure he’s not 100 percent happy. I think he still thinks of himself as a starter, but he’s a pro. I think he’s a guy that’ll do anything to help the team.”

Walker has started 217 of his 227 appearances in 13 major league seasons. He started six times this season when Suarez was hurt to an ERA under 3, then moved to the bullpen for two three-inning relief appearances, then returned to the rotation in place of Nola. He threw four innings on Friday and should be ready to relieve by Tuesday or Wednesday in Toronto.

He’s never worked on a reliever’s schedule, and Thomson anticipates it’ll take some three-day and two-day rests to acclimate to the workload. A fastball averaging 92.3 miles per hour this year could see some improvement in shorter bursts, and his six-pitch mix could be sharpened for shorter outings, with more play on a potentially elite splitter.

The Phillies need the help. Their most reliable reliever just got his ERA out of the 8s. Jose Ruiz, DFAed on Sunday, joined the lengthy list of relievers who couldn’t parlay one successful season into more (move over Connor Brogdon and Andrew Bellatti).

Ruiz had been a candidate to fill the third right-handed spot behind Romano and Kerkering. But an 8.16 ERA failed that examination. Now it’s Walker’s turn.

Sunday’s decisions serve two purposes.

The Phillies need relief help at the trade deadline, but it’s unrealistic to think they’ll land more than two guys worthy of a postseason roster. If Walker can be a competent reliever, maybe they only need one. He’s auditioning for that job, as is Seth Johnson, as is Max Lazar.

A four-man postseason rotation would turn two starters into relievers, possibly Suarez to reinforce the left side and Painter the right.

Giving Walker a month in the bullpen not only kills more time on his four-year, $72-million contract, but it helps the Phillies evaluate internal options before dipping into the market.

The side effect is to boost Abel’s trade value as trade bait or to get him used to the bigs and comfortable enough to possibly shift him into a relief role.

The questions are clear, if tricky. The Phillies have two months to try out the answers.

Contact Matthew De George at mdegeorge@delcotimes.com