OAKLAND -- For someone who didn’t get to participate in any intrasquad or exhibition games due to a delayed start to Summer Camp, Jesús Luzardo did not appear to have any rust in his 2020 debut.

Making his first appearance of the regular season in the sixth inning of Saturday’s 4-1 loss to the Angels at the Oakland Coliseum, Luzardo came out blazing, striking out Justin Upton on three straight fastballs 97 mph or higher to begin his outing. The rookie did his best to keep the A’s in the game, twirling three scoreless innings of relief.

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“For a guy that has been sitting in his room for a while, to give us [44] pitches and not give up a run, there were a lot of good things that tested him,” said A’s manager Bob Melvin. “He came through with flying colors, throwing 98 mph, and all his pitches. I’m glad we were able to get him up.”

Luzardo’s appearance was reminiscent of his previous outing at the Coliseum, in which he also tossed three scoreless innings out of the bullpen in the A’s Wild Card Game loss to the Rays last October. The 22-year-old lefty utilized a five-pitch mix on Saturday to get through the three frames with two strikeouts on 44 pitches.

The scary part: Luzardo didn’t even feel like he had his best stuff, admitting that the explosiveness of his pitches felt better coming out of his hand in a live batting practice session before a Summer Camp exhibition game against the Giants.

“I picked up where I left off last year,” Luzardo said. "I tried to keep the same routine and what I was doing in those long relief outings last year.”

A starter by trade, Luzardo, Oakland’s No. 1 prospect per MLB Pipeline, has gotten quite used to pitching in relief. He threw solely in that role during his time with the A’s last season as a September callup. Originally slated to move into the starting rotation this season, he now finds himself in the bullpen again for the start of the 2020 campaign after a positive COVID-19 test delayed his arrival to Summer Camp by two weeks.

But is there a chance Luzardo’s next outing comes as a starter? Melvin did not rule out the possibility.

“We’ll see,” Melvin said. “I think nowadays, if you can throw 60 to 65 pitches, you might be in a position to start. We’re right on the border there, so we’ll see. We’ll have a decision to make at some point. Maybe we get him one more outing and we’re in a good position to start him, or maybe not.”

Luzardo will happily perform in whatever role is asked of him. But in terms of shaking off the cobwebs and getting on the mound for what would be his first Major League start, the left-hander said he is ready now.

“I feel like I am [ready] just based on how my arm feels and the strength of my arm right now,” Luzardo said. “I felt good throughout the outing.”

Sean Manaea, who started the game, retired 12 of the first 13 batters he faced, but he began to unravel in the fifth. Recording the first two outs of the inning, the Angels mounted a rally with three runs on back-to-back doubles by Andrelton Simmons and David Fletcher to give Los Angeles a 4-0 lead. The double by Fletcher was the knockout blow as Manaea was pulled thereafter at 55 pitches.

The first four innings were encouraging for Melvin, who was pleased with the uptick in Manaea’s velocity on a fastball that touched 90 mph several times after it sat around 87 mph during his final exhibition outing last week.

“He was great, and then it just happened pretty quickly with three batters that he left balls in the middle of the plate,” Melvin said. “Looked like he had better life on his fastball and all his pitches. When you only score one run, sometimes a couple hitters on the other team dictate where the game goes.”

The A's were stifled by Angels starter Dylan Bundy, who limited them to one run over 6 2/3 innings. Their only offense came in the seventh inning on an RBI single by Robbie Grossman that plated Stephen Piscotty, who doubled earlier in the inning on top of making a solid robbery of Mike Trout in the fifth.

Oakland’s best chance came in the eighth, as Marcus Semien and Ramón Laureano led off with back-to-back singles against Ty Buttrey, though that momentum was quickly zapped as Matt Chapman grounded into a double play to end the threat.

“We were one good at-bat away from putting real pressure there with the middle of our order,” Melvin said. “We didn’t swing the bats great. You gotta give Bundy a lot of credit. He mixed it up really well against us and used all three of his pitches effectively. “