OAKLAND -- Luis Barrera was desperate for a chance to redeem himself.

His day couldn’t have started any worse. Entering the first game of Saturday’s doubleheader against the Angels as a pinch-runner in the seventh inning of a tie game, Barrera ran the A’s out of the inning by getting doubled off on a shallow flyout by Elvis Andrus. Just minutes later, the outfielder’s mishaps carried over on defense in the eighth, overrunning a single to left field by Andrew Velazquez for an error that extended the Angels’ lead to two runs.

With the A’s trailing by two and his spot in the batting order due up fifth in the bottom of the ninth, Barrera’s possible redemption seemed unlikely. However, a two-out rally sparked by Ramón Laureano’s double and Christian Bethancourt’s walk set the stage against Angels closer Raisel Iglesias. Barrera got his moment and took full advantage, clobbering a 1-1 slider from the right-hander for a three-run blast over the Coliseum’s right-field wall for a walk-off 4-3 victory over the Halos -- his first Major League home run.

“Baseball gods are real,” said A’s starter Paul Blackburn, whose superb outing of one run allowed in 6 2/3 innings lowered his ERA to 1.67 on the year. “That’s incredible, honestly. I couldn’t be more happy for [Barrera]. He comes to the ballpark every single day with a smile on his face. He’s always working hard and trying to prove he belongs here.”

From the moment Barrera committed his error in the eighth, he immediately received positive reinforcement from Laureano, who ensured him he’d get a chance to redeem himself later in the game. When Barrera made his way from the on-deck circle to the plate in the ninth, he received more encouragement from Bethancourt.

“Laureano kept telling me to stay ready for my turn,” said Barrera. “Bethancourt told me he was going to try hard for a walk to give me that chance. When he went to first base, he told me, ‘Vamos! Tu eres el hombre’ ('Let’s go, you’re the man!') and, thankfully, I hit that home run.”

There was good reason for Barrera to believe this opportunity with the A’s would never happen. It was just over a month ago on April 11, less than 24 hours after hitting a walk-off home run for Triple-A Las Vegas, that he was designated for assignment by the club.

Barrera is rated Oakland’s No. 23 prospect per MLB Pipeline, so to say the news of his designation came to him as a shock would be an understatement. The 26-year-old outfielder vividly recalled what was the lowest moment of his professional baseball career.

“They called me that Monday before our flight to Salt Lake around 8:30 a.m. and told me I was DFA’d and was off the roster,” Barrera said. “I just said, ‘Wow.’ I was having a good season in Las Vegas, so I felt a little sad. A little down.”

Throughout the five-day period in which he was in virtual no-man’s land as he was placed on waivers, Barrera received support from his wife, Marlene Collado, who kept his spirits up through the process.

“I went five days without playing,” Barrera said. “Around the third or fourth day, I was talking to my wife and she picked me up. She told my career was not over yet. It’s all about my mindset. I tried to get past the DFA and took it as a fresh start from zero.”

Going unclaimed on waivers, Barrera received a new beginning with the A’s on May 9, when he was added back to the 40-man roster and recalled from Triple-A, where he was batting .286 with three homers, six doubles, a triple and 10 RBIs in 23 games this season. With the DFA serving as a wake-up call, Barrera also returns with a new mentality.

“I think Luis has matured a lot,” A's manager Mark Kotsay said. “We kind of sent the message that in order to get back here, he had to establish a better work ethic and understanding of what is required on an everyday basis here. He’s grasped that, and it’s good to see him having success early.”

Getting a start in right field for Game 2, Barrera continued his success at the plate by collecting a pair of singles as he reached base in all three of his plate appearances in the A's 9-1 loss.