LONDON -- Rob McElhenney hopped Chase Utley’s hedges last week in Los Angeles.

He needed to get the ball that his kid kicked into Utley’s yard.

Almost 15 years ago, McElhenney’s character Mac on “It’s Always Sunny in Philadelphia” wrote a love letter to Utley, hoping to one day have a catch with him. It is one of the show’s most popular episodes and an iconic moment in Philadelphia pop culture because of its relatability (an adult who loves a professional athlete he has never met), its absurdity (Mac put stickers at the bottom of the letter, hoping it would help) and its unabashed love for the Phillies. The episode spawned a real-life friendship between McElhenney and Utley, which showed up again Sunday afternoon at the London Series at London Stadium.

“It’s wild,” McElhenney told MLB.com on Sunday. “He moved into my neighborhood, and now we’re next-door neighbors. People are like, ‘Oh, he’s in your neighborhood.’ No, he’s my next-door neighbor.”

McElhenney, Utley and Bryce Harper recently starred in a 2024 London Series promo, where Utley learns that McElhenney has been writing Harper daily letters about having a catch with him, continuing the storyline from “The World Series Defense” episode in 2009. McElhenney explains to Utley in the promo that Harper not only is a clutch player, but his beard is like “golden lamb’s wool.”

(Matt Leuthe wrote the lamb’s wool line. He is the head of creative at More Better, which is McElhenney’s production company.)

The spot ends with Utley issuing McElhenney an ultimatum.

Choose him or Harper.

In the end, Mac got both. Before Sunday’s game, McElhenney walked to the mound to throw the first pitch to Utley. But McElhenney’s wife, Kaitlin Olson, who also stars in “It’s Always Sunny,” jogged to the mound to have a conference with Utley and her husband.

Harper then appeared from the dugout and jogged to first base. Olson rolled a ball to McElhenney at shortstop, who underhanded the ball to Utley at second. Utley fired a throw to Harper at first to complete what they called the “first ceremonial 6-4-3 double play.”

“Obviously for Chase and everything that he’s done for this organization, obviously I’m going to say yes, just because it’s Chase Utley,” Harper said last week on The Phillies Show podcast. “’[It’s Always] Sunny in Philadelphia,’ that’s one of the top episodes. People love that episode. Just being able to kind of be part of that, I was like, obviously. This is really, really cool.”

McElhenney said he was blown away at how Utley and Harper nailed their lines.

“You never know how the athletes are going to act, but they both crushed it,” he said.

McElhenney and Utley first met when Utley and Ryan Howard made a cameo in an episode of “It’s Always Sunny” in 2010.

“When the writers pitched it to me, I thought, ‘That’s a really cool opportunity to have one of my favorite players on the show,’” McElhenney said. “I had no idea if he’d do it. Sometimes when you go to the agents, they just turn down everything. Or they say, ‘How much?’ We’re a small show without a huge budget. I actually got in touch with John [Powers] Middleton [Phillies managing partner John Middleton’s son]. He connected me with Chase, and Chase was in.

“So when Chase and Ryan came to the set, Jen [Utley] also came. Kaitlin got to meet Jen, and we hit it off. We went out to dinner with them. That’s when we realized, ‘Oh, these are our people. These are definitely our people.’ My wife is from the Pacific Northwest. I’m from Philly. They’re from California. You don’t know if this is going to work out. But we went to a restaurant in Rittenhouse Square and just had a blast.”

Utley and his family have spent nearly the past two years living in London. They plan to return to Los Angeles eventually.

Maybe the Harper-Utley-Mac storyline continues then? Or was Sunday the end?

“I don’t know,” McElhenney said, smiling. “I think it’s just the beginning.”