The Argentina international became only the third player to be sent off in the cup final during the latter stages of yesterday's shock defeat after receiving a second booking, with Ben Watson's late winner securing Wigan's first major trophy.
Zabaleta admitted that City's players had been surprised by how their opponents performed, and had been unable to overcome the spirit of the Wigan players.
"The worry over the future of Mancini did not affect us," Zabaleta said.
"Wigan surprised us. They played with a lot of desire and we could not break down their spirit."
Manchester City substitute Jack Rodwell admitted that his side failed to perform adequately during the final, but urged his team-mates to respond.
"We knew it was going to be a tough game, especially on such a big pitch but we just weren't at the races today," Rodwell said.
"We're going to have to bounce back now. We have a game on Tuesday and we want to make sure we finish in second place."