Roethlisberger told the Pittsburgh Post-Gazette the ankle injury was aggravated during Sunday's 13-9 victory over Cleveland, in which he played the entire game.
"I felt really good going in the Cleveland game," he said. "I had a little setback early in the third quarter, so we're working really hard right now with the trainers and doctors to get back to even where we were before the Cleveland game."
The Steelers' signal-caller said he's confident "we'll be all right" in time for Pittsburgh's wild-card playoff game Sunday at Denver.
He first hurt the ankle Dec. 8 in another game against the Browns. He played the entire next game against San Francisco and then was held out of a Dec. 24 contest against St. Louis before returning last week.
Roethlisberger has gone 48-of-84 through the air for 551 yards, no touchdowns and three interceptions during his past two games, the newspaper said.
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