DENVER -- There were a lot of moments over the previous two years when it was hard for the Giants staff to watch Hunter Pence struggle, but no place seemed to bother him as much as Coors Field. There were games here where it seemed he simply couldn't see the ball at the plate or in right field.

As Bruce Bochy sat in the visiting clubhouse at Coors Field on Wednesday, he recalled how Pence sometimes had issues defensively here, noting that it's a difficult place for a lot of visiting outfielders. He also talked about Pence's resurgence, which has not surprised the manager.

Pence hit a pinch-hit grand slam earlier in the day in Pittsburgh, giving him five homers and 21 RBI in his first season with his hometown Texas Rangers. He has as many homers as any Giant but Kevin Pillar, and as many RBI as Pillar, the team leader.

Pence, primarily a DH for the rebuilding Rangers, has a .344 average and is slugging .656. Last year, the final one of his five-year deal with the Giants, he hit .226, with a .332 slugging percentage, four homers and 24 RBI.

Pence looked done for much of last season. But at the age of 36, he won a job with the Rangers with a huge spring.

"That man, he has willed his way through a lot of things," Bochy said. "I'm not surprised by anything he does. You're talking about a changed player, too. Here's a man who played Winter Ball to try to fix his swing and get right."

[RELATED: Why Mac will get long look in left field for Giants]

Pence tried to change his swing in the middle of the season last year and then rededicated himself to it as soon as his run in San Francisco ended, even playing in the Dominican Republic for the first time to test the changes. Bochy said he can see the improvement.

"He's quieter, he's quieter at the plate," Bochy said. "A lot of the 'drift forward' is out. He's not jumping (at the ball) quite as much as he was (here)."