Cole Irvin wasn’t supposed to be here. When the A’s traded cash for him in January, he was viewed as little more than a depth piece. Even when he excelled in Spring Training and earned a rotation spot in place of a then-injured Mike Fiers, Irvin called it a “temporary” fix.

Well, Fiers is healthy. And Irvin’s spot in the rotation doesn’t look or feel nearly as temporary.

“He made his case in Spring Training and he’s still making his case,” A’s manager Bob Melvin said. “We could do things a little differently going forward, you know, try to get [Fiers] in there at some point to start. But [Irvin] has certainly pitched well enough to stay in the rotation.”

Wednesday’s 2-0 loss to the Rays was hardly the fault of Irvin, who pitched six innings of two-run ball and collected a career-high eight strikeouts. In his past three starts, Irvin has allowed just three runs (1.56 ERA) while walking two and fanning 20.

• Box score  

On this night, Irvin tiptoed around mild threats from the Rays through four innings, allowing four hits and two runners in scoring position. In the fifth, he was one pitch away from his first perfect frame, before Mike Zunino launched an outer-edge fastball up off Tropicana Field’s catwalk for a home run.

Irvin then dealt a full-count walk to Brett Phillips in the next at-bat, followed by a pair of singles -- the second of which scored Phillips -- before finally escaping with a popout.

Two runs. Fifteen extra pitches. And because of another quiet night from the offense, that’s all it took for Irvin to fall short of three consecutive victories.

“If we score five, we’re talking about how good he pitched,” Melvin said after the A’s were shut out for the first time this season. “Obviously we just couldn’t solve [Rays starter Tyler] Glasnow.”

Irvin flashed his best stuff in his sixth and final inning, striking out the side with three swings through his sinker. That’s a pitch he didn’t even use with the Phillies in 2019, his only other full season in the Majors, and it’s a big reason why the A’s think Irvin has unlocked something special.

“I think what we’ve allowed him to do that he maybe didn’t do in Philadelphia was allow him to use his best pitches, what he feels most comfortable with,” Melvin said before the game.

Sure enough, Irvin’s sinker has gone from a non-existent offering to his most used pitch in a span of two seasons. Against the Rays, it garnered four whiffs on 15 swings (27% whiff rate) and seven called strikes, helping him navigate the defending American League champion’s lineup largely unscathed.

Irvin wasn’t just out there battling the Rays, though. He’s also been “dealing with some [pollen] allergies that kind of knocked me on my butt” since Monday. He said he felt pretty good during his start despite not being able to breathe out of his nose.

From an overhaul of his pitch mix, to an unexpected rotation spot, to a bout of seasonal allergies, Irvin has handled a variety of adversity so far this season and conquered it accordingly. He said he’s not interested in questioning his role right now, instead preferring to let his work every fifth day speak for itself.

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Entering 2021, Irvin had a 6.75 ERA across 45 1/3 career innings. He got off to a rocky start this season, allowing eight earned runs in his first two outings, but things are looking much smoother of late.

Still, Irvin knows he still has a lot to prove: to the A’s, who are giving him a chance; to the Phillies, who gave up on him; and to himself, the one who will ultimately dictate what comes next.

“I’ve got a chip on my shoulder from past years,” he said. “It’s not necessarily going on with this team, but it’s more so I’ve got a chip on my shoulder to prove to myself and to some other people that I won’t mention. But I’m here to stay.”