ST. PETERSBURG -- Mitch Spence was being pushed to his limit and probably a little beyond.

The A’s rookie didn’t complete five innings or throw more than 77 pitches in either of his first two Major League starts. Through five innings during Oakland’s 3-0 victory Tuesday against the Rays at Tropicana Field, Spence was already at 81 pitches. And he wasn’t done yet.

How could he be? He was crafting a no-hitter.

“The biggest thing when you know you're kind of close to the end, I just try and go out by out,” Spence said. “It’s like, ‘OK, these are the last guys I’ve got to get. I’ve got to push a little extra to get through the sixth inning.’”

Spence’s venture into uncharted territory began with an 11-pitch at-bat against Rays catcher Ben Rortvedt that ended when the right-hander froze Rortvedt with an 83 mph slider at the top of the zone.

His night finally came to an end on his 98th pitch, another slider that shortstop José Caballero blooped into center field for Tampa Bay’s first hit of the game.

In just his third career start, Spence became the second A’s pitcher this season to carry a no-hitter through five innings; left-hander J.P. Sears held the Rangers hitless for 6 1/3 innings on April 11. It was the first time that an A’s rookie starter had thrown at least five no-hit innings since Joe Boyle on Sept. 30, 2023.

“It's definitely a confidence booster,” Spence said. “You’ve got to have a little bit of blind confidence when you're going out there. It doesn't matter who's in the box; your stuff is good enough to get anybody out. So having success early on definitely does help.”

This performance is also a big help for Oakland’s injury-riddled rotation. Spence logged 11 appearances and 25 1/3 innings out of the bullpen before he got the nod for a spot start against the Royals on May 17. That opportunity became available because the A’s were missing Alex Wood, Paul Blackburn and Joe Boyle from their rotation. Ross Stripling has since joined them on the injured list.

Spence combined for 7 2/3 frames with 10 hits and three runs allowed through those first two starts. His previous outing, May 22 vs. the Rockies, included three walks in only three innings. Having better command of his cutter and his slider was his main focus heading into Tuesday’s assignment. And he was in command with those offerings.

Spence threw a cutter or a slider on 78 of his 98 pitches, and that combination led to him giving up only four hard-hit balls, retiring 16 of the 18 batters he faced and not allowing a runner to advance past first.

“I think the cutter, it just gets off the barrel,” manager Mark Kotsay said. “He pitched effectively with the cutter and a slider tonight, which is kind of the game plan for him.”

“Mitch is a good pitcher,” said Rortvedt, who was teammates with Spence when both were playing for the Yankees’ Triple-A Scranton/Wilkes-Barre affiliate last year. “He cuts the ball pretty well. He's kind of unorthodox in the way he throws. … He just did a good job at mixing all his pitches, filling up the zone, keeping people off balance.”

Spence’s memorable night also resulted in his first win as a Major League starter. The A’s offense couldn’t muster any run support until the sixth inning, when Miguel Andujar hammered a sweeper from Rays starter Zack Littell over the short wall in left field for a three-run homer.

The home run, which was Andujar’s first since Sept. 17, 2023, came off his bat at 105.8 mph, per Statcast. It was Andujar’s first extra-base hit with the A’s after making his team debut on May 24.

It was the A’s only run-scoring swing of the game. But with the way Spence was pitching, they needed only one.

The 26-year-old has obviously earned himself another turn in Oakland’s rotation. While his first two starts had some bright spots, this latest performance was a huge leap forward. He has proven that he can pitch into the sixth inning. He has proven he can handle close to 100 pitches. Kotsay may not have been comfortable with Spence reaching either of those benchmarks coming into Tuesday’s game.

But sometimes, you just have to let a good pitcher keep going.

“Pushing him even to 95 [pitches] was a tough decision,” Kotsay said. “But he was throwing the ball really well, and you still liked his stuff. For a young pitcher, sometimes they can do more than what we think they can, and there's a good chance that, his next start, we'll see the same thing hopefully.”