PHILADELPHIA — The adjustment was more of a tweak, something that emerged from numerous between-starts bullpen sessions designed to calm any fears that Luzardo was tipping his pitches. Luzardo and a few Phillies pitching coaches settled on this — he’d hold his glove higher and closer to his chest before coming set. It was something he had to do only from the stretch.

It is harder, now, for a runner on second base or the opponent’s first-base coach to see Luzardo’s grip. But, in the five starts since Luzardo unveiled the new delivery, it’s harder for him to throw strikes from the stretch.

That’s an issue.

“Obviously, we’re already midseason, so there’s no adjustment period,” Luzardo said. “You have to figure it out.”

Luzardo couldn’t make it through three innings again in a 9-6 Phillies loss to the Cincinnati Reds. He faced six batters in the third inning and did not retire a single one. Cincinnati scored five runs. That was the game.

There is an outsized focus on the Phillies’ rotation because it has been so good. It has carried this club. It is, essentially, the key to any October success. The Phillies could send three starters — Zack Wheeler, Cristopher Sánchez and Ranger Suárez — to the All-Star Game. But they demoted their fifth starter, Mick Abel, to the minors Friday morning. Then they watched Luzardo stumble.

The Phillies have far greater concerns than their 27-year-old lefty. The lineup has familiar holes. The bullpen has craters. The outfield’s defense is among the worst in the sport. But, given the construction of this roster, Luzardo has importance. Maybe he’s starting a postseason game. Maybe he’s a late-inning bullpen weapon.

Right now, he just has to be better. He has a 9.49 ERA in his last seven starts, which include the “tipping” incidents and the mechanical fallout from them.

Since Luzardo adjusted his mechanics from the stretch, after the June 5 start in Toronto, he’s seen a drastic gap in his performance:

• No runners on base (68 plate appearances): .226/.294/.242, 6 walks, 23 strikeouts
• Runners on base (59 plate appearances): .423/.492/.692, 7 walks, 11 strikeouts

On Friday, Luzardo could not land his hard slider or the sweeping one for a strike. He had to challenge Cincinnati’s hitters with fastballs. Often, he left them up in the zone. They hit him hard.

Luzardo was fine in the first inning when he didn’t permit a runner to reach base. He needed only 11 pitches to retire the side, and that included two strikeouts. The trouble started in the second inning when he issued a one-out walk. In the third, the Reds went infield single, walk, single, double, double, single. That’s when Rob Thomson couldn’t let Luzardo absorb any further damage pitching from the stretch.

“I know it’s something that they’re working on,” Thomson said. “But I think he’s comfortable. He has to be able to throw strikes out of the stretch.”

Every conversation about Luzardo has to include his mounting workload. He’s reached 97 1/3 innings, his third-most in a big-league season. He’s already thrown 100-plus pitches in seven starts — his most in any season. He’s held his velocity, but the wayward command could be more than a mechanical thing.

Or not.

“I feel great,” Luzardo said. “I still feel strong and healthy, which is a positive. But I need to find ways to limit deep counts. Try to get in and out of innings as fast as possible.”

Luzardo is averaging almost 20 pitches per inning since his mechanical adjustments.

“He needs to get back in the zone a little bit more, for sure,” Thomson said. “Induce some swings and contact. Soft contact. I don’t think he’s hunting strikeouts. But it would be nice to be a little more efficient.”

The Phillies have a chance to provide Luzardo with a larger in-season break. He’s slated for one more start, Wednesday in San Francisco, before the All-Star break. They could slot Luzardo fourth in the post-break rotation, which would give him 11 days between starts. Luzardo could use that time to recharge — and to refine his new delivery from the stretch with side work.

Everyone needs it to work, especially the front office. Until hitting a speed bump, Luzardo was Dave Dombrowski’s most shrewd offseason acquisition. The rest — Max Kepler, Jordan Romano and Joe Ross — haven’t added much. There is pressure on the front office to erase a lack of aggression over the winter by swinging a big trade in July.

But even if Dombrowski nets a reliever with swing-and-miss stuff or a platoon bat for the outfield, the onus is on the current core. Everyone — not just Luzardo — has to discover consistency. That is probably too big of a request.

So is putting it all on the rotation. The Phillies are a .500 club (15-15) since June 1 despite a 2.80 ERA from the rotation. That is more than a half run better than the next-closest rotation. It feels like the Phillies have squandered something — at the very least, a chance to put more distance between them and the New York Mets in the National League East race.

There will be days like Friday when the rotation needs some help. Until then, it’s on them. Luzardo has to solve his mechanics on the fly.

“I still have all the confidence in the world in Luzardo,” Thomson said. “Everybody’s going have bad outings here and there. I think we’re still fine.”

(Top photo: Mitchell Leff/Getty Images)