SAN FRANCISCO -- Jaylin Davis saw his average dip below .100 at one point Wednesday night, and as he looked out at DJ Johnson with one out in the ninth, the scoreboard read .125. But the rookie outfielder never lost his confidence or his swagger.

The second the ball left his bat, Davis took a big hop and started his first big league home run jog. It was the kind of reaction you would expect from someone who hit 35 homers in the minors this season.

"I got the pitch I was looking for and it felt great off the bat," Davis said. "I definitely knew I got it."

The blast to dead center gave the Giants a 2-1 win over the Rockies and a memorable first homer for Davis, a 25-year-old acquired from the Twins at the deadline. He couldn't remember his last walk-off at any level. Now he has one in the big leagues. Davis became the first Giant to hit a walk-off homer for his first big league blast since Fran Healy in 1971.

Jaylin Davis called game: pic.twitter.com/IZ2I98RwbZ — Alex Pavlovic (@PavlovicNBCS) September 26, 2019

Davis is one of several young players the Giants had hoped would break out this month, but he had spent most of September smothering balls, hitting grounder after grounder. Occasionally his speed would lead to an infield hit, but Davis was still looking for his first extra-base hit entering play Wednesday.

The Giants never really got worried, and on several occasions Bruce Bochy mentioned to Davis that even Willie Mays started his career with a slump. On the last homestand, Davis met with Mays, who had one hit in his first 26 career at-bats. Mays told Davis to relax and have fun. Everyone knew the power would flash eventually.

"What he was doing down there in Sacramento -- it's hard to do that unless you have a tremendous gift to hit a baseball," Bochy said.

[RELATED: Lincecum has to be at Bochy's last game as Giants manager]

The homer gave Bochy another one-run win as he heads for the exit. And it gave Davis' new teammates a little extra sleep.

"We didn't want to go extra innings tonight," Davis said, smiling.