‘I didn’t want to leave:’ Zach Eflin couldn’t rejoin the Phillies. Maybe now, with the Rays, he can beat them.

Zach Eflin isn’t ashamed to admit it: He pays close attention to the Phillies. Like really close. He follows their social media accounts and scans their box scores. He even cheers them on.

After seven seasons, old loyalties die hard.

“I’m still so close to a lot of guys on the team,” Eflin said in a phone conversation over the weekend. “I care about their careers. I care about how that team does. I don’t think I need to sugarcoat it or hide it. At the end of the day, man, I root for the Phillies.”

And Tuesday, he’ll do all he can to beat them.

» READ MORE: Phillies questions at midseason: Bryce Harper’s power outage, trade deadline outlook, and more

It’s business, not personal. Just like when the Phillies’ inaction after the World Series signaled to Eflin that they didn’t intend to pick up their end of his $15 million mutual option. The 29-year-old right-hander became a free agent, signed with the Rays, and will face the Phillies — against close friend Aaron Nola, no less — on the Fourth of July at Tropicana Field.

“I’m super-excited,” said Eflin, a groomsman in Nola’s wedding last December. “It’s going to be really, really weird. But it’s going to be really cool to have that experience.”

For weeks, maybe even a month, Eflin peeked at the schedule and counted the days to see if he would line up against his former team. It crystallized two weeks ago, when the Rays pushed back ace Shane McClanahan to rest a lower back injury and put Eflin on track to start the series opener.

Then, last Thursday, the morning after Eflin pitched in Arizona and Nola in Chicago, they texted each other to confirm.

“I’m going to have to make a bet with him or something,” said Nola, proposing with a laugh that dinner might be on the loser. “But no, it’s going to be good to see him and Lauren and maybe the [twin] babies. Definitely miss the guy, man. I was with him for so long. Definitely one of my best friends. I’m just happy that he’s doing good and he’s healthy.”

Indeed, Eflin is proof that the grass sometimes really is greener, a fact that may not be lost on Nola if, as expected, he reaches free agency after the season.

In accepting the Rays’ three-year, $40 million offer, Eflin not only secured the largest deal for a free agent in Tampa Bay club history but also got an opportunity to play only about 120 miles west of his home near Orlando, a convenience for when he and Lauren need help with their 2-year-old daughter, Ashton, and 3-month-old twin girls, Austen and Hallie.

» READ MORE: The tall tale of Carlos De La Cruz: How the Phillies’ 6-9 slugger has become an unlikely top prospect

Eflin also joined the Rays, who do more with less than any team in baseball. This year, they have the most wins (57) and best record (57-30) in the American League despite a luxury-tax payroll of approximately $127 million, according to Cot’s Baseball Contracts. (The Phillies are pushing $250 million.)

Oh, and Eflin has benefited from Tampa Bay’s progressive pitching program. His 3.29 ERA in 15 starts would be leading the Phillies’ rotation. He ranks at or near his career-best totals in most other metrics, including fielding independent pitching (3.24), walks/hits per inning pitched (1.030), walks per nine innings (1.5), strikeout rate (25.6%), and home-run rate (2.8%).

“I can’t give you any secret sauce or anything, but I would honestly say, the No. 1 thing is the culture of the organization,” Eflin said. “They truly don’t ask you to change much. They just ask you to listen to a couple of things. If you’re willing to, great; if not, great. There’s no added stress or pressure at all.”

With the Phillies, Eflin said he was never inclined to trust analytics and technology. And the instability of having five pitching coaches in a five-year span (2017-21) did little to sell him on a specific philosophy.

But after the Rays committed to him, Eflin wanted to be open-minded to their approach. The result: A reconfigured pitch mix that incorporates more curveballs and cutters to augment his signature sinker. He has thrown fewer change-ups and sliders and all but ditched his four-seam fastball.

“I’ve always been super old-school, kind of a ‘screw the numbers, screw anything else, I just want to go out and compete’ kind of mentality,” Eflin said. “But signing a three-year deal with a team that wanted to invest in me, I wanted to invest in them as well. I came with open eyes and ears, ready to learn, and I’ve been so much more into the analytical side.

“Not overwhelmingly, but more just the way pitches are moving, the shapes of pitches, what grips you can use to get more depth or more lateral movement. It’s been cool to dive into.”

» READ MORE: How much will it cost the Phillies to keep Aaron Nola beyond 2023?

Mostly, though, Eflin can trace his success to better health. He had surgery on both knees in 2016, a procedure in 2021 to repair a torn patellar tendon in his right knee, and another knee injury last season that caused him to miss 2½ months. He made more than 25 starts and threw more than 150 innings only once with the Phillies.

Eflin returned from his knee problems last September to join the bullpen, even closing out the victory that clinched the Phillies’ first playoff berth since 2011. But when his agent asked about the mutual option after the World Series, the Phillies “said they hadn’t talked about it,” according to Eflin.

“That didn’t necessarily sit well with me,” Eflin said. “After that, we heard from them, I think it was one time, saying they were going to go after a big-market free-agent starting pitcher.”

The Phillies wanted a mid-rotation starter with more durability and settled on a four-year, $72 million deal with free agent Taijuan Walker.

Nola’s situation is different. He talked with the Phillies in spring training about a contract extension, but agreed to table negotiations because the sides were far apart. It’s believed that Nola and the Phillies still want to work something out.

“[Eflin] was disappointed, and I could see why, right?” Nola said. “He’s been here, second-longest-tenured guy besides me. This is a great organization and what we did last year. But he also knows it’s the business of baseball.”

» READ MORE: The Phillies’ Noah Song has begun a rehab stint in the minors. And then what? That’s complicated.

It also makes Tuesday more than just another start for both pitchers. But especially for Eflin.

“I wasn’t looking for a fresh start anywhere else,” he said. “Early in the offseason, if we were having this conversation, I would’ve wanted to be with Philly no matter what. I didn’t want to leave. But things happen.”

So, Eflin couldn’t (re)join the Phillies. Maybe he can beat them.