During the game, Martin was taken for X-rays, which came back negative. Martin hopes to return soon, but Yankees manager Joe Girardi strongly hinted that rookie Jesus Montero will catch for the Yankees on Sunday.
"It's bruised," Martin said. "It was to the point where I couldn't really feel the baseball in my hand, and I tried to throw to second base and didn't really have any feeling. We're going to see how it feels [Sunday]."
Posada entered in the third inning, strapping the gear on in a game situation for the first time all year, including Spring Training. His last game behind the plate was Game 6 of the 2010 American League Championship Series against the Rangers.
The 40-year-old veteran was almost immediately tested by the Angels' Howard Kendrick, who attempted to steal second base, and Posada threw out Kendrick for the first out of the inning.
"I knew they were going to attempt, so [you] just be prepared, be ready," Posada said. "It's been a while, but I just got rid of it."
Because of concern over repeated concussions, Posada had been relegated to emergency backup status, behind Martin and Francisco Cervelli.
But Cervelli was scratched from Saturday's starting lineup due to concussion symptoms of his own, and Montero -- the other catcher on New York's roster -- was serving as the designated hitter.
"I told him it was like riding a bike -- go ahead and get back on the bike," Girardi said. "He wasn't so sure he believed me when he went back there, but he did a nice job."
The foul tip off Martin's thumb came off the bat of Maicer Izturis and drew blood, but Martin stayed in the game to complete the second inning.
However, Martin airmailed his throw to second base into center field while warming up CC Sabathia in the third, at which point Girardi called Martin back into the dugout.
"Obviously, today was an emergency," Posada said. "Cervy is down, Montero is DHing and you've got Martin banged up. I'm glad that [Martin's] X-rays are negative. I'm really happy for that for him."