Luis Severino talks to pitching coach Larry Rothschild and catcher...

Luis Severino talks to pitching coach Larry Rothschild and catcher Gary Sanchez during the pitchers implosion in the first inning against the Oakland Athletics on September 5, 2018 in Oakland, California. Credit: Getty Images/Ezra Shaw

OAKLAND, Calif. — That American League wild-card game the Yankees are still pretty much certain of playing in Oct. 3, and likely against the A’s?

Hard to imagine, at least currently, how the Yankees can consider starting Luis Severino in it.

The 24-year-old righthander, whose first half had him firmly in the mix as Cy Young candidate, saw his nightmarish second half continue Wednesday night as he lasted a season-low 2 1/3 innings in an 8-2 loss to the A’s in front of 21,004 at Oakland Coliseum.

“I need to do a better job,” said Severino, who allowed six runs (five earned) and six hits. “Right now I’m not at my best. I need to perform like I was in the first half.”

The Yankees (87-53), managing all of five hits, fell 9 1/2 games behind the Red Sox in the AL East and saw their lead over the A’s, who won two of three in this series, cut to 3 1/2 games for the top wild-card slot.

Severino received little help in a four-run first inning from Gary Sanchez — he had as bad an inning as a big-league catcher can have as there were two wild pitches and two passed balls — troubles the pair blamed on cross-ups because they changed signs before the game.

“There were a couple cross-ups, but at the end of the day they were near the zone and I feel as a catcher, I have the ability to stop those,” Sanchez said through his translator. “And I didn’t.”

Though Sanchez’s defense appropriately commanded plenty of attention — he’s been charged with 13 passed balls, tying him for most in the majors — focusing solely on that obscures a larger problem:

Severino, now 17-7 but with the highest ERA he’s had this season (3.52), hardly resembles the pitcher who as recently as July 1 was 13-2 with a 1.98 ERA.

“We have a few weeks for that kind of stuff to unfold and see where we’re at and we’ll make those decisions as we go,” Boone said, asked if he’d be comfortable starting a Severino/Sanchez batters in a one-and-done wild-card game. “But do I know those two are capable of going out and shoving? Absolutely.”

Severino went 2-4 with a 7.50 ERA in seven games from July 7-Aug. 13, but showed some signs in his next three starts — a 3.78 ERA and 26 strikeouts compared to four walks — of turning things around.

Then came Wednesday, which showed that progress to be a mirage as four of the first five A’s to the plate had hits.

“A bunch of stuff,” Severino said of what went wrong in the first. “A couple of cross-ups with the signs. It was a mess.”

After the Yankees left the bases loaded in the first against Mike Fiers — they did make him throw 28 pitches — it quickly came apart in the bottom half as the A’s

Leadoff man Ramon Laureano started the inning by driving a 0-and-1 fastball over the head of Brett Gardner in left for a double, the first of six doubles for the A’s, who came in second in the Majors in doubles (282). Matt Chapman grounded to short but, with Jed Lowrie at the plate, Laureano went to third on a passed ball. Lowrie then stung a 3-and-1 slider to right, the RBI single making it 1-0.

Khris Davis followed by launching one to right where, off the bat, Andrew McCutchen seemed to lose the ball, which sailed to the base of the wall for a double.

With Matt Olson at the plate, Severino threw a 0-and-1 fastball that came in low and 98 mph that scooted under Sanchez for a wild pitch, allowing Lowrie to score to make it 2-0 and put Davis on third. Olson took a 2-and-1 fastball opposite field off the top of the wall in left, the RBI double making it 3-0.

Stephen Piscotty swung and missed on a 2-and-1 slider but it got by Sanchez for another passed ball. Severino’s next delivery, a slider, bounced for a wild pitch, which brought in Olson to make it 4-0.

Fiers, after walking Sanchez to load the bases with two outs in the first, settled, retiring 15 of the next 16 he faced. The righthander walked Aaron Hicks to start the seventh and Sanchez ripped his first homer since June 20, his 15th overall, to make it 8-2. Fiers (11-6, 3.36) allowed three hits over six innings.

Chapman walked to start the third and Lowrie singled. After retiring Davis on a fielder’s choice and Olson via strikeout, Piscotty’s broken-bat single to center brought in two runs to make it 6-0 and end Severino’s night. Chapman’s RBI ground out in the fourth off Jonathan Holder made it 7-0, and back-to-back two-out doubles by Laureano and Chapman in the sixth made it 8-0.

“I’ve been disappointed with the way I’ve played lately, I’ve been disappointed with the way the team’s played,” Gardner said. “I know I’m capable of doing better, I know the team’s capable of doing better. It’s up to us to try and figure things out and turn things around.”

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