Luis Severino of the New York Yankees talks to catcher...

Luis Severino of the New York Yankees talks to catcher Gary Sanchez after throwing a wild pitch against the Oakland Athletics in the first inning at Oakland Alameda Coliseum on September 5, 2018 in Oakland, California. Credit: Getty Images/Ezra Shaw

SEATTLE — Luis Severino said “it’s not about who’s catching,” but good luck convincing Yankees fans of that.

Severino’s second-half slide continued Wednesday night in an 8-2 loss to the A’s, a game that featured a disastrous four-run first inning in which Gary Sanchez was charged with two passed balls and saw two wild pitches get past him. One of the latter easily could have been ruled a third passed ball.

Both pitcher and catcher blamed the ugly inning primarily on cross-ups, the result of changing signs, but the night brought back all of the concerns surrounding Sanchez and his career-long difficulty in stopping balls consistently.

“We were using a new set of signs and we definitely had a little bit of trouble getting on the same page in that first inning,” Sanchez said through his translator. “Can definitely say there were some pitches there I should have done a better job of blocking them.”

Severino, who lasted a season-low 2 2⁄3 innings, used the phrase “it was a mess” to describe it, then invoked the catcher he threw to while Sanchez was on the disabled list from July 24-Aug. 31 (and also from June 25-July 19).

“I’ve been working with [Austin] Romine for a long time [this season] and we used different signs,” Severino said.

When asked if he’d rather throw to Romine, Severino said: “It’s not about who’s catching.”

It is not unusual for teams to change signs, and it is something that happens far more frequently than those on the outside are aware of.

“I need to do a better job. I need to communicate more with Gary,” Severino said.

The pair had a well-publicized issue in a July 24 game at Tropicana Field when Sanchez got crossed up on a slider and the ensuing wild pitch allowed a runner to score from second.

“That was on me, 100 percent,” Severino said later, acknowledging he misread Sanchez’s sign, which was for a fastball.

Regardless of who was at fault Wednesday, there are bigger concerns for the Yankees.

One, naturally, is Sanchez, who, despite missing so much time, is tied for the league lead in passed balls (13) with Houston’s Martin Maldonado.

By all accounts, Sanchez has put in the work to improve defensively, and there have been periodic indications of progress. In his first three games back, for example, there were no wild pitches and one passed ball.

“We’ve got to dive in and look at if there’s something we see mechanically that was a reason for [Wednesday], we’ve got to dive into that, but I do feel like he’s made progress in where he’s at [defensively],” Aaron Boone said. “The way he’s receiving the ball, the way he’s framing, the way he’s getting some strikes for us. In some of these games since he’s come back . . . I feel he’s been really efficient defensively, but we have to keep working at it.”

Just as big a concern, and in the big picture arguably bigger, is Severino. He is 17-7 but has a 3.52 ERA, the highest it’s been this season, and is nowhere close to the pitcher who was 13-2 with a 1.98 ERA on July 1. (In the vast majority of those games, it should be pointed out, he was throwing to Sanchez.) In 11 subsequent starts, he is 4-5 with a 6.83 ERA and has allowed 76 hits, including 13 homers, in 55 1⁄3 innings. Opposing hitters have a .323/.360/.574 slash line against him in that span.

With the Yankees staring at the Oct. 3 wild-card game, likely against the A’s, there’s little chance that they will throw the current iteration of Severino  in that game. J.A. Happ and Masahiro Tanaka, based on recent performance, certainly would rank ahead of Severino.

“I think we’re concerned but I also think we’ve seen enough signs that feel like he’s started to climb out of it a little bit,” Boone said. “[Wednesday] obviously was a little bit of a bump in the road and a setback for him that we have to dive into. We have to all come together and fix it because he’s so important to us.”

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