New York Yankees manager Aaron Boone, right, argues with home...

New York Yankees manager Aaron Boone, right, argues with home plate umpire Ed Hickox after being ejected during the fifth inning of a baseball game against the St. Louis Cardinals Sunday, Aug. 7, 2022, in St. Louis. (AP Photo/Jeff Roberson) Credit: AP/Jeff Roberson

SEATTLE — After the Yankees lost at home to Boston in 11 innings on July 15, catcher Jose Trevino took stock of his team.

The Yankees were a major league-best 62-28 but had lost five of six — their worst stretch of the season at that point.

“A little adversity never hurts anybody,” Trevino said that night. “I think we’ll be fine.”

About three weeks later, the Yankees have not yet reached the “fine’’ stage, and that adversity no longer can be accurately described as “little.”

Pause for context: Entering Monday night’s opener of a three-game series against the Mariners at 70-39, they still were comfortably ahead in the AL East with a 9 ½-game cushion over the Blue Jays.

But for a variety of reasons, this current iteration of the Yankees hardly resembles the club that stormed from the gates and at one point looked as if it might win 120 games, or even more.

The Yankees brought a season-high five-game losing streak into the Seattle series and are fresh off a three-game sweep at the hands of the Cardinals.

They were 9-16 in their last 25 games, 21-23 in their last 44 and a half-game ahead of the Astros for the best record in the American League. After the games of June 18, when the Yankees were 49-16, they led Houston by nine games.

Diagnosing the issues doesn’t take much digging.

A starting rotation that was dominant during the first three months has fallen off dramatically.

Gerrit Cole has been terrific in stretches but also has mixed in a surprising number of clunkers. Luis Severino is out until at least mid-September, Jameson Taillon hasn’t showed signs of coming out of his slump and Nestor Cortes is on an innings limit in the second half.

Frankie Montas lasted only three innings in his first start as a Yankee on Sunday. However, any reasonable person would affix an asterisk to that, given that he was making his first start since July 26 and arrived in St. Louis late Saturday night after going on the bereavement list because of the death of his mother-in-law.

The bullpen, while still possessing plenty of quality arms, hasn’t produced anything close to the level of excellence Aaron Boone enjoyed in the first three months of the season.

The loss of Chad Green early and Michael King more recently cost the Yankees two relievers in whom Boone had complete trust in high-leverage situations. During the first three months, he seemingly had four, even five relievers earning that trust. With Clay Holmes’ struggles of late, that number may well be down to zero. New additions Scott Effross and Lou Trivino should help, but it’s too soon to draw any conclusions about them.

The offense, while still potent, clearly misses Giancarlo Stanton and Anthony Rizzo.

In the clubhouse — where there still is some residual head-scratching, not to mention anger, about the trade of Jordan Montgomery to the Cardinals — the reaction to the skid has been panic-free.

“We’re definitely going through it right now,” DJ LeMahieu said Sunday. “Frustrated with how we’ve played but still feel really good about our team and how we’ve done this year as a whole.”

Just after the deadline, Boone was asked how much an already good team had been improved by the new acquisitions — Montas, Trivino, Effross and outfielder Andrew Benintendi.

“I mean, on paper, we’re better,” he said. “But I will caution that that’s just on paper. We have to go out and do it still, and go out and prove that.”

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