Luis Barrera's two-out, three-run home run in the bottom of the ninth inning lifted the Oakland A's to a 4-3 victory over the visiting Los Angeles Angels in the first game of a doubleheader on Saturday afternoon.

The Athletics trailed 3-1 heading into the bottom of the ninth and the Angels had closer Raisel Iglesias on the mound. Iglesias, who entered the game a perfect 8 for 8 in save opportunities, retired the first two batters of the inning and got ahead in the count 0-2 to Ramon Laureano.

Laureano worked the count to 2-2 before hitting a double to right-center.

Iglesias (1-1) then walked Christian Bethancourt, bringing to the plate Barrera, who had one hit all season. But Barrera got ahold of a slider on a 1-1 pitch and hit it over the fence in right field for his first career major league homer and a walk-off win for the A's.

The Angels were in position to win the game after a two-run eighth inning snapped a 1-1 tie. Anthony Rendon and Mike Trout were not in the lineup to begin the game, but both entered the game as pinch hitters in the inning.

Trout came to the plate with Jared Walsh on first and one out. After Walsh took second on a passed ball with Trout at the plate, Trout was then walked intentionally.

Rendon followed with a pinch-hit single to left field off A's reliever Zach Jackson to drive in Walsh and put the Angels up 2-1.

Andrew Velazquez followed with a single to left, Trout taking third. But when Oakland left fielder Barrera mishandled the ball for an error, Trout scored and the Angels increased their lead to 3-1.

A's reliever Lou Trivino (1-2) earned the win. Brandon Marsh led the Angels offense, reaching base four times with three hits and a walk, while Shohei Ohtani added two hits.

Angels starter Jhonathan Diaz threw 4 2/3 scoreless innings, allowing just one hit and walking four. His performance wasn't unlike his only other start this season, when he threw five scoreless innings and allowed three hits and four walks on May 6 against Washington.

Diaz and the bullpen got support from the Angels defense, which turned four double plays. And Angels center fielder Aaron Whitefield, spelling Trout, made a diving catch of a sinking liner hit by Sean Murphy to end the sixth inning.

A's starter Paul Blackburn gave up one run and five hits in 6 2/3 innings.