"It's been bothering him for a while," Astros interim manager Tony DeFrancesco said. "They finally shut him down."
Martinez said his left hand has been a nagging problem since the beginning of the season. The pain subsided with ice treatment, so Martinez didn't think much of it. Recently, though, the pain got worse.
When he faced the Pirates' Jeff Locke on Friday, he realized that he couldn't play well with the pain. He struck out in both at-bats against Locke and hasn't played since.
"He was throwing the ball and I couldn't even catch up to it because of the pain," Martinez said. "I just told [DeFrancesco] to take me out."
Doctors examined Martinez's hand and determined he had a small fracture in the hamate bone. The surgery will remove the hook of the hamate bone. The Astros still hope Martinez can play winter ball after rehabilitation, which is fairly common among baseball players.
"Right now, it's kind of up in the air just because they say rehab is about six weeks," Martinez said. "I'm not sure if the [timing] is going to be appropriate."
Martinez hit .241 with 11 homers and 55 RBIs in 395 at-bats this season after hitting .274 with six homers and 35 RBIs in 208 at-bats last season. He refused to blame the down numbers on the injury.
"I don't think that's fair," Martinez said.
Outfielder Justin Maxwell needs six RBIs in the final nine games to capture the team lead. Martinez's 55 RBIs would be the second fewest by a team leader in the National League since 1969, excluding strike seasons. Cleon Jones had a team-leading 52 RBIs for the 1972 Mets.