Marcus Stroman has home run regrets after latest shaky Yankees start

Marcus Stroman was shaky for the fourth time in his last six starts and was again hurt by the home run in Thursday’s 8-4 loss to the Reds at the Stadium.

Stroman regretted what he said was a slider on the outside part of the plate that Spencer Steer hit into the right-field seats for a three-run homer in the fifth inning.

The right-hander had given up a pair of solo home runs, and not much else, until that point — but it continued a poor run by the once-standout rotation.

“I’ve got to be better in that fifth and give us a chance there,’’ Stroman said. “I was one pitch away from keeping it to two runs. I didn’t do my job.”

The three homers allowed were the most Stroman has given up this season and tied a career-high.

He’s not alone in struggling in that department.

“A lot of our mistakes are ending up in the seats,’’ Aaron Boone said. “It’s spoiling some outings.’’

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And Stroman’s ERA, which was 2.73 six starts ago, is up to 3.58.

Stroman also acknowledged having Cincinnati speedster Elly De La Cruz on base is a distraction.

“He for sure takes a lot of focus,’’ Stroman said. “It feels like he steals bases very easily, so you have to have a priority on timing [and] slide steps, so you end up losing your focus on the hitter a little bit.”

Trent Grisham’s error on a Jeimer Candelario single to center in the top of the ninth was especially ugly, with Grisham appearing to go after the ball without much urgency.

“I just played back on it as opposed to coming to get it,’’ Grisham said. “I just made a mistake. It’s frustrating in that situation.”

Grisham plays center field in a similar manner to the way Gleyber Torres plays second base — with a nonchalant appearance — and it’s cost both of them recently.

Boone, though, didn’t take issue with Grisham’s approach.

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“It’s one of those that looks bad in the moment, especially with what we’re going through as a team right now,’’ Boone said. “It’s also the way Trent Grisham, Gold Glover, plays center field, with a relaxed, easy nature.”

Boone acknowledged he wasn’t happy Candelario got to second base because of Grisham’s mistake, but stood by the outfielder.

“He has a track record of outstanding play out there and that’s the way he does it,’’ Boone said. “With kind of a slow heartbeat [and] motor.”

Jon Berti (left calf strain) is expected to accompany the Yankees to Tampa when they begin a series Tuesday.

The infielder will work out at the facility and “hopefully” get some live at-bats, Boone said.

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If all goes well, Berti could begin a rehab assignment “at some point right after the [All-Star] break,” Boone added.

The versatile infielder has been out since injuring his calf May 24.

Giancarlo Stanton ran on the field before the game and is “just starting to ramp up the baseball activities,” Boone said.

Stanton, out since June 22 with a left hamstring strain, is still at least a few weeks away from a return.

Boone said he did not have a timetable for Stanton but he believes the rehab is “going pretty well.”

Austin Wells hit his fourth home run — and second in his last five games — with a solo shot in the fifth as his production at the plate picks up. … Alex Verdugo entered in a 6-for-47 rut but matched his season-high with three hits — including a pair of doubles.

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