Has Jesús Luzardo been tipping his pitches? He and the Phillies think so.

PITTSBURGH — With a runner on second base and two out in the second inning Thursday, Jesús Luzardo threw a low-and-in fastball that Toronto’s Tyler Heineman lashed for an RBI double.

It was almost as if Heineman knew it was coming.

Upon further review, maybe he did.

Luzardo spent the weekend watching video of his last two starts, and they were as gruesome as he remembered. But the Phillies also believe they made a discovery: Luzardo might have been tipping pitches.

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“We found some tipping stuff and found some game plan stuff that teams definitely had, without a doubt,” Luzardo said Sunday. “Now it’s just a matter of fixing that.”

It didn’t take Sherlock Holmes to realize something was amiss. Through 11 starts, Luzardo allowed a total of 19 runs in 67 innings. He gave up 20 runs in 5⅔ innings in the last two starts against the Brewers and Blue Jays.

The Phillies dug into Luzardo’s stuff and found no change. His fastball velocity, for instance, averaged 96.6 mph, consistent with his overall mark of 96.4 mph. His sweeper spun at a rate of 2,239 revolutions per minute, almost identical to his 2,234 rpm rate for the season.

Luzardo maintains that he’s healthy, even though he has already surpassed his innings total from an injury-marred 2024 season with the Marlins. If he wasn’t, there would likely be a drop-off in his stuff.

The Phillies dug deeper, and well, let Luzardo explain.

“It’s just something that they could pick up,” Luzardo said. “It might be from the hitter, it might be guys on second base; it could be from the base coaches. It could be coming from all three places at times. It depends really on the situation of the game. But definitely there were situations there, with multiple teams.”

Luzardo recalled uncovering a similar issue in August 2023, when he gave up 13 runs over two starts with the Marlins. In that case, it was a movement with his hands that was clueing in hitters about what was coming.

Was it an easy fix?

“Theoretically it should be, yeah,” Luzardo said.

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But he also added that solving a mechanical issue comes through repetitions in throwing sessions, initially on flat ground, then off the bullpen mound, and eventually in a game situation.

“It’s good finding out what could be the problem,” Luzardo said. “But until you go out there and do it, there’s not really that peace of mind.”

Luzardo will have an extra day before he’s scheduled to start Wednesday against the high-powered Cubs at Citizens Bank Park. The Phillies hope that will be enough time to shake the bad habit.

“When you’re on the mound, you’re in that fight-or-flight [mode] to where you go back to the muscle memory of things that you’ve done over and over,” Luzardo said. “It’s more of just being mindful of focusing on what we want to do, and then when I get on the mound, kind of the same thing over.”

Zack Wheeler is scheduled to start Monday night against the Cubs, according to manager Rob Thomson.

Wheeler has not pitched since May 29 against the Braves. He went on the three-game paternity list Tuesday, then was transferred to a family-leave list over the weekend.

Thomson said Wheeler threw a bullpen session Saturday at Citizens Bank Park to prepare for his return.

Wheeler has a 2.96 ERA in 12 starts.

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Aaron Nola did not throw over the weekend because of lingering soreness in his side. He’s scheduled to see team doctors Monday in Philadelphia.

Nola’s sprained right ankle, which has sidelined him since May 16, has felt better. But he didn’t face hitters in a scheduled live batting practice session last week because he got sick and developed the soreness in his side.

“He doesn’t remember throwing a pitch or anything where he felt it,” Thomson said. “[The trainers] think it’s from coughing, and he just upset something in there.”

Thomson said he’s comfortable with using starter-turned-reliever Taijuan Walker on back-to-back days, something the veteran righty hasn’t done in his career. After pitching one inning Thursday in Toronto, Walker told Thomson he was available Friday night in Pittsburgh. “The attitude’s been great,” said Thomson, who noted the Phillies have seen an uptick in Walker’s velocity out of the bullpen, too. ... The Phillies claimed right-hander Ryan Cusick off waivers from the White Sox and optioned him to the rookie-level Florida Complex League. Cusick, 25, had a 6.32 ERA last season in triple A. Right-hander Kyle Tyler was designated for assignment to open a 40-man roster spot for Cusick. ... The Phillies will face Cubs lefty Matthew Boyd (5-3, 3.01 ERA) at 6:45 Monday night.