SAN FRANCISCO — Heliot Ramos thought he’d just leg out an infield single to lead off the ninth inning with the score tied. He wound up circling the bases to win the game, capping his mad dash by diving across home plate in dramatic fashion.

Ramos’ infield single followed by two Texas errors that led to a little league homer gave the San Francisco Giants a 3-2 win over the Rangers on Sunday. It was the Giants’ fifth walk-off win of the year, and it was, by far, the most unorthodox.

“It’s been a minute,” Ramos said of the last time he rounded the bases in a similar way.

Ramos tapped the first pitch he saw from Rangers reliever Luke Jackson softly toward third. Jackson barehanded the ball and flung it wildly past the dive of Jake Burger at first. Ramos slowed down as he rounded second, thinking that Burger had already retrieved the ball.

But, Burger was just picking up the ball in foul territory down the right-field line. Ramos saw third-base coach Matt Williams furiously waving him to continue — and he kept going. Burger’s throw to third was also off the mark, skipping down the left-field line and allowing Ramos to easily scamper home.

“I thought he had the ball already, and then I saw Matt waving me in, and I just kept going,” Ramos said.

Ramos’ hesitation at second helped him in the end.

“He was unaware when he went to second that he could’ve been easily at third,” Giants manager Bob Melvin said. “Once he was aware of that, then they had to make the play on him. For whatever reason, it all worked out about as good as it could. If he knew, he’d just be standing on third with nobody out. But sometimes things happen for a reason and the theatrics were pretty cool there at the end.”

Ramos added: “I was trying to play it safe, but I guess I had it.”

Ramos joked that the team was probably going to replay the sequence over again during the hitters’ meeting and “make fun of me.”

The Giants improved to 19-10 to maintain a slim lead in the competitive National League West.

Melvin, who added that he has never seen a game end that way, said that the Giants have done a good job of giving themselves a chance to win this season by not “beating themselves” — primarily behind good pitching and defense.

“If we hang around long enough, we find a way to win a game,” Melvin said. “That’s kind of a new way.”