J.T. Realmuto or … who? The Phillies will face a complex decision with their star catcher.

In assessing the Phillies’ needs this week, Dave Dombrowski ran through a positional checklist. Bryce Harper at first base ... Alec Bohm at third ... Trea Turner at shortstop ... and so on, around the All-Star-laden horn until he got to catcher.

Then, he lingered for a moment on J.T. Realmuto.

“He’s working like crazy already,” Dombrowski said, unsolicited. “He has put himself in a position where he’s ready to go. He’s down in Clearwater, working out every day.”

Swell. Was anybody doubting him?

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Realmuto is as in tune with his body as any player in baseball. He works out six days a week in Florida (he lives a few miles from the Phillies’ facility) and adheres to a detailed training program before and after games. Neither his fitness nor work habits is ever questioned.

But Realmuto will turn 34 in March and had surgery on his right knee twice in five years, including the removal of torn cartilage in June. The three-time All-Star is also coming off his worst season at the plate since 2015, capped off by an 0-for-11 series in the divisional round loss to the Mets.

Oh, and he’s going into the final season of a five-year, $115.5 million contract.

The Phillies haven’t approached Realmuto about an extension, but it may come up later in the offseason or spring training. And it will be a fascinating conversation.

Because although there are reasons to believe Realmuto will age more gracefully than a typical catcher, contracts of more than two years for catchers in their mid-30s are as common as total eclipses. Here’s the list:

With Realmuto, Kyle Schwarber, Jordan Romano, and possibly José Alvarado and Matt Strahm eligible for free agency after next season, the Phillies could lop as much as $65 million off the payroll. Considering they will likely close in on the $301 million fourth luxury-tax threshold in 2025, they would surely welcome future flexibility.

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But Realmuto remains the Phillies’ on-field quarterback. Pitchers swear by his game-calling and rely on his guidance. Teammates often refer to him as the “backbone” of the roster. After Zack Wheeler, he’s the club’s most indispensable player.

There isn’t a successor in the wings, either. Not after trading Logan O’Hoppe in 2022. Garrett Stubbs hasn’t started 60 games in a season; fellow backup Rafael Marchán has a troublesome injury history. Top catching prospect Eduardo Tait is 18 years old and in A-ball.

And the step down from Realmuto to the next-best options on next year’s presumptive free-agent market — Jacob Stallings, Gary Sánchez, and Victor Caratini — is more like a cliff dive.

Given all of that, it’s difficult to imagine the Phillies wouldn’t lock up Realmuto before it gets that far. But how much will it take — in terms of years as much as dollars — to make it happen?

Four years ago, the Phillies couldn’t keep Realmuto from free agency.

After trading for him from the Marlins in 2019, they made attempts at an extension. But then-agent Jeff Berry wanted Realmuto to be paid relative to all position players, not just catchers, and the sides didn’t get close to an agreement.

Realmuto became a free agent after the 2020 season, and the timing wasn’t ideal. As many teams cut back amid reduced revenues from 60 games played without fans, the market wasn’t as robust as his camp hoped.

Still, he landed a record contract — for a catcher, that is.

» READ MORE: From 2021: Inside the Phillies’ long-awaited union with J.T. Realmuto

In January 2021, after hiring Dombrowski to run baseball operations, the Phillies re-signed Realmuto to a $23.1 million average annual salary, the highest ever for a catcher but only by $100,000 over Joe Mauer’s extension 11 years earlier.

The contract has already produced surplus value. In addition to playing 147 more innings (not including the postseason) and compiling more wins above replacement than any catcher since 2021, Realmuto has been worth $123.5 million, according to Fangraphs’ WAR-to-dollars formula.

Even so, there are signs of slippage. From 2018 to 2022 — age 27 to 31, and including the first two seasons of his present contract — Realmuto batted .272 with 96 homers and an .814 OPS, 19% better than league average. In the last two seasons (age 32-33), he batted .258 with 34 homers and a .757 OPS, only 7% above the mean.

The Phillies believe they can help boost Realmuto’s production by better managing his workload behind the plate. He averaged 122 starts over the last eight full seasons, including 130 in both 2022 and 2023, and was on pace for that volume again last season before injuring his knee.

With an extra day off per week, manager Rob Thomson said, “I think his numbers will get better.”

Thomson is waiting until he sees Realmuto to propose the idea and said the Phillies “don’t know how he’ll react.” It’s a safe bet Realmuto will push back, like any ironman catcher.

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Maybe it would help to cite the example of Salvador Perez. The Royals talked Perez into a slight reduction in his workload in 2021 before signing him to a four-year, $82 million extension at age 31. And he has nearly as many homers (121) and a higher OPS (.783) over the last four seasons than he did in the previous six (125, .738).

“Sal was a little reluctant at first,” recalled Royals senior advisor Mike Arbuckle, a former Phillies assistant GM. “He told us he would still like to be back there and catch 130-140 games. It was, ‘That’s my position. That’s what I’ve always done.’ But when he saw what it was taking off his legs, he realized it would keep him fresher and it didn’t take him long to adjust. But that’s a tough conversation with any player.”

Especially if he’s playing for his next contract.

In 2013, the Phillies re-signed a popular catcher who was two months shy of turning 35 and declining as a hitter.

“Is it a risk to put three years into a catcher at this stage of his career? It can be, yes,” then-general manager Ruben Amaro Jr. told reporters after bringing back Ruiz. “Clearly, this is a commitment that will be scrutinized. But when we start talking about this position, and the dearth of quality at this position, I know that Chooch knows what it takes to be a championship-caliber player, to bring a championship to this city.”

You can almost hear those words spilling from Dombrowski’s mouth.

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The Phillies overpaid Ruiz, who caught 109 games in 2014, 83 in 2015, and got traded to the Dodgers midway through the season in 2016.

The catcher aging curve is almost always unforgiving.

Yet some metrics suggest Realmuto is defying it with his uncommon athleticism. His sprint speed, elite among catchers, was nearly identical last season (28.4 feet per second) to his rookie year (28.8). His pop time, the measure of how fast a catcher releases the ball on steal attempts, is the best in baseball eight years running. He was actually quicker on the draw last season (1.85 seconds) than in his first five years in the majors.

So, maybe Realmuto’s offensive dip last season was simply a down year, not a reflection of the toll of catching.

Realmuto put in long hours last winter in the biomechanics lab at the Phillies’ spring-training complex to fix a flaw in his swing. He thought the changes were working last season but injured his knee while legging out a triple on May 4 and played through it for six weeks. When he gave in to surgery, he was batting .261 and slugging .411 with a .720 OPS.

After returning on July 20, he hit .272 and slugged .451 with a .788 OPS.

“I think it was more just fatigue through the course of the year than the injury,” Thomson said. “But he’s 100% [in the offseason].”

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The two best free-agent catchers this winter signed two-year contracts: 34-year-old Kyle Higashioka ($13.5 million from the Rangers) and 35-year-old Travis d’Arnaud ($12 million from the Angels). Neither is as accomplished as Realmuto, whose floor would figure to be Molina’s extension at age 35.

And that deal was signed seven years ago.

Last spring, the Phillies took Wheeler off the market one year before he could’ve been a free agent by signing the 34-year-old ace to a shorter-term (three years), high-AAV ($42 million per year) deal. Maybe they could use a similar structure for Realmuto, boosting his annual salary in exchange for capping the contract at three years.

Regardless, the conversation might start in the next few months — and without much precedent to help serve as a guide.