OAKLAND, Calif. -- During the dark days of his long rehabilitation while recovering from two separate tears to his right Achilles tendon, Michael Soroka imagined a triumphant comeback on the mound.

Finally back in the majors Monday night, Soroka took his first loss in three years. But he sort of won anyway.

The right-hander tossed six innings for the Atlanta Braves in his long-awaited return to the big leagues, pitching for the first time since a devastating series of injuries to his lower leg.

"Today was a big one," he said, "a day like today and the people that believed in me. I always said I was going to be back here for the people that believed in me, not the ones that said I couldn't."

Soroka was called up from Triple-A Gwinnett by the National League East leaders to start the series opener against the Oakland Athletics on Memorial Day -- a whopping 1,030 days between outings for the Braves' 2020 Opening Day starter. He allowed four runs on five hits, struck out three and walked two. Soroka left trailing 4-1, and Oakland (11-45) won 7-2 to stop an 11-game skid.

It felt like even longer that he hadn't pitched because of the pandemic-shortened 2020 season.

"When I think about how long ago it really was, to be honest with you, we can even go back to 2019 because there was nobody in the stands in 2020 so it didn't really feel like big league baseball that year," Soroka said.

The 25-year-old pitcher received cheers from Braves fans as he ran out to the mound for the bottom of the first to make his first major league appearance since Aug. 3, 2020, then calmly retired the side in order on 13 pitches and received a standing ovation from the loud Atlanta fans.

"It's been a whirlwind, and I'm kind of excited to put that storyline behind us now and get back to putting up zeros," Soroka said.

Left fielder Eddie Rosario made a leaping catch at the wall to start the second, robbing Aledmys Diaz of a home run as a delighted Soroka acknowledged the play and celebrated.

"Let's go, Michael!" one fan yelled.

Soroka didn't allow a hit until Jonah Bride's one-out single in the third but quickly loaded the bases with another single and a hit batter. He emerged unscathed after inducing Seth Brown's inning-ending double play.

But then Soroka plunked Shea Langeliers with a pitch to begin the fifth and gave up an RBI single to Esteury Ruiz before Ryan Noda's three-run homer put Oakland up 4-1.

Sean Murphy had staked Soroka to a 1-0 lead with an RBI single in the first against his former team.

Soroka went 13-4 with a 2.68 ERA in 2019 to finish second in NL Rookie of the Year voting and sixth for the Cy Young Award. He first tore his Achilles on Aug. 3, 2020, and then had more hard luck. A setback led to a follow-up surgery, then he tore the same Achilles again while rehabbing midway through the 2021 season.

This spring, Soroka had another complication in his comeback because of a hamstring injury. He said he is grateful to everybody who supported his tough journey.

"There's been some people in my corner for a long, long time that have stuck by me," Soroka said. "It's a day for them, too. Those were the people that kept me going."