SAN FRANCISCO — It’s Wilmer Flores’ world and everyone’s just living in it.

A night after hitting three homers and driving in eight runs, Flores delivered a walk-off win in the bottom of the 10th inning by drawing a nine-pitch, bases loaded walk against All-Star Mason Miller to deliver the Giants a 1-0 win over the Athletics.

Landen Roupp delivered his best outing in roughly a month, throwing six shutout innings with five strikeouts. Roupp was matched by the Athletics’ Luis Severino, the owner of the largest contract in Athletics franchise history who also pitched six shutout innings with five strikeouts.

For most of the game, both pitching staffs were in lockstep with one another.

Roupp and Severino each threw six scoreless innings apiece. Randy Rodríguez and Justin Sterner pitched put up zeros in the seventh inning. Tyler Rogers retired the side on four pitches in the top of the eighth, then Sterner kept the game tied with another scoreless frame in the bottom of the eighth. That set the stage for the ninth.

Ryan Walker retired the side in order in the top of the ninth on seven pitches, his first 1-2-3 inning since May 3. The Athletics’ Tyler Ferguson did the same, striking out Matt Chapman and Willy Adames in the process. To extra innings the ballgame went.

Following the quick innings of Rodríguez, Rogers and Walker, Camilo Doval was responsible for the 10th inning with the automatic runner on second base. Doval retired the first two batters he faced but walked Jacob Wilson on four pitches, putting runners at the corners for the perpetually dangerous Brent Rooker.

Doval threw a first-pitch ball, creating anxiety among the sellout crowd, but responded by striking out Rooker with a low-and-outside slider to end the inning, hitting his signature hop as he walked off the mound.

In the bottom of the 10th, the Giants had Adames as the automatic runner on second base with LaMonte Wade Jr., Patrick Bailey and Tyler Fitzgerald due up against All-Star Mason Miller. Wade drew a leadoff walk, putting runners at first and second with no outs, then Bailey laid down a sacrifice bunt to put runners at second and third with one out.

Miller recorded the inning’s second out by striking out Fitzgerald, and after the intentional walk of Mike Yastrzemski, Flores stepped to the plate with an opportunity to play hero. And hero he played.