Gerrit Cole allows 6 runs, 3 HRs in first inning of Yankees loss

The game had begun Wednesday at Yankee Stadium, but it looked more like the Mariners were taking batting practice the way they were easily launching rockets to the seats off Gerrit Cole in the top of the first.

It couldn’t have started worse for the Yankees’ ace. After seven batters, Cole had served up three homers, good for six runs.

Luis Castillo, the ace the Yankees were interested in acquiring from the Reds before the trade deadline, was making his Seattle debut after the team dealt four minor-leaguers for him. And Aaron Judge was getting a rest day.

There would be no comeback. Cole turned into his All-Star self again after the first, allowing no runs over his final five innings. But it was indeed too late. Castillo held the Yankees to three runs and five hits and fanned eight over 6 2/3, and the Mariners claimed the rubber game with a 7-3 win.

“It’s kind of hard to believe it blows up so quick,” Cole said. “I’m trying to be excellent out there and obviously I’m not. Obviously the game’s letting us know we’re not there.

“So we’ve got to keep grinding on it. It doesn’t feel good. We let a series get away from us because of a very poor first inning today. That’s on me.”

Cole also fired five shutout innings in his previous start against the Royals, but he yielded five runs in his other inning, which was the fifth.

“That’s what we’ve got to dive into a little bit more because that’s what’s kind of hurt him a little bit is the big inning,” Aaron Boone said. “It’s been mostly dominant, even in those games like today. … But it’s on all of us to make sure we’re able to limit the damage where we’re finding our way a little bit.”

Adam Frazier opened the first for Seattle (57-49) by grounding a single into right-center. Then Jesse Winker walked on five pitches.

The next pitch was a hanging slider. Eugenio Suarez smacked it at 109.4 mph. The souvenir sailed 390 feet to the leftfield seats.

Carlos Santana stepped in. Cole threw him a 3-and-1 fastball at 98.7 mph. Santana hit it harder at 107.6 mph. The ball made it to the right-center bleachers, 423 feet from where the flight started.

Four batters, 4-0 Mariners.

J.P. Crawford was next. He lined a hanging curve into left for a single.

One out later, ex-Mets prospect Jarred Kelenic sent a changeup to the rightfield seats — 6-0.

“Looking back, I think we could’ve used the fastball a little more,” said Kyle Higashioka, who had the view from behind the catcher’s mask.

The Yankees, who went 4-3 on this homestand, were on their way to falling to a still AL-best 70-36 and Cole was on his way down to 9-4. He got the final two outs before being booed off the mound.

From there, he gave up two singles and no walks and posted six of his eight strikeouts. After Kelenic’s homer, he retired 17 of his last 19 batters.

But Castillo (5-4) was mostly in command throughout. The 29-year-old righty was tagged for an RBI single by Isiah Kiner-Falefa in the second and a two-run homer by Higashioka on his 109th and final pitch.

“His stuff is always really good,” said Higashioka, who also doubled in the second. “His fastball had a lot of life to it. I got lucky that he gave me a couple of pitches to hit.”