Now, less than a year after retiring, he's got a new title: owner.
The Giants announced Wednesday that the 35-year-old former catcher has joined the ownership group. Posey, while not announcing the percentage, said he bought in with his own money. He's also joining the six-person board of directors.
Posey is the first former player to be at the Giants' principal partner level.
"I couldn't be more thrilled," Posey said.
Giants manager Gabe Kapler saw parts of the news conference in San Francisco while preparing for Wednesday night's game at Colorado.
"So good for our organization to have a player's perspective on our board and making an impact in important decisions," Kapler said. "It's just makes us better."
While Posey said he won't be "in the trenches" with ownership, he plans to be a "sounding board" for chairman Greg Johnson and the rest of the 31-person ownership group. Posey said he didn't envision joining ownership until after the career .302 hitter ended his 12-year career in 2021.
"Not only do we get the benefit of a youthful perspective, but somebody who has played in the field and worn the orange and black," Johnson said. "We are privileged having him as part of the ownership group."
Posey begins his new role as the Giants complete a disappointing season. They are 72-77 after Wednesday night's win and are 9 1/2 games out of the final NL wild card with 13 games remaining.
"I'm excited to provide my insight," Posey said. "Being a player for the San Francisco Giants, I understand there's expectations and that's great."
Johnson said there are some "gaps that need to be addressed" with the roster. He said the team does not yet have player budget for next season but plans to try to bolster the roster through free agency.
"As you know, we have a lot of flexibility coming into this offseason," Johnson said. "And we're well aware of the shortstops and the person who can hit in the Bronx is out there."
After throwing 5 1/3 no-hit innings in the Giants' 6-1 win against the Rockies, right-hander Logan Webb was asked if he thought he impressed his new boss.
"I actually texted him and said I know who to talk to when I hit free agency," Webb said, smiling. "No, I'm excited for him. ... It's a good thing. When Buster's around, it's different. I kind of wish he was still playing, but it's better when the San Francisco Giants have Buster Posey a part of them."
"There is time to improve upon that," he said.