PRO FOOTBALL : Young Impresses in 49er Victory, 24-13 : Interconference: Despite broken thumb, he passes for 240 yards and three touchdowns against Steelers.

Steve Young had to persuade the San Francisco 49ers he could play with a broken thumb on his passing hand. He didn’t have to convince the Pittsburgh Steelers.

Sunday, Young won a battle between quarterbacks who were recovering from injuries, passing for 240 yards and three touchdowns to lead the 49ers past the turnover-stricken Steelers, 24-13.

Young, not given the go-ahead to play until midweek, connected with Jerry Rice on two touchdown pass plays following a Steeler turnover as the 49ers took a 17-0 lead in less than 16 minutes.

The thumb that Young broke Aug. 8 against the Raiders swelled before the game, so he asked center Jesse Sapolu to snap the ball into his right hand to alleviate the pressure on his passing hand.

“I was a little concerned in warm-ups when it swelled up, but it was fine during the game,” said Young, the NFL’s highest-paid player. “It just feels funny, but I think we’re through the woods with it now.”

Rice made touchdown catches of five and six yards in a 5:15 span of the first half--the record 104th and 105th of his career--and finishedwith eight receptions. The 49ers started three of their first four drives inside the 50 with the help of Michael McGruder’s interception and Keith DeLong’s recovery of a Barry Foster fumble.

“When you play the best, you see how far you have to go to be the best,” Steelers cornerback D.J. Johnson said. “They teach you a lesson in execution. If you let them, they’ll execute to perfection.”

Young completed 24 of 36 passes for 240 yards and had three passes intercepted.

Young threw a five-yard scoring pass to Brent Jones after a disputed encroachment penalty against Pittsburgh that TV replays appeared to show was incorrect.

On the play before the touchdown, right tackle Harry Boatswain appeared to jump offside on third and nine from the 10. But referee Gordon McCarter called linebacker Kevin Greene for encroachment although there was no contact along the line of scrimmage.

Mike Tomczak, making his first start for Pittsburgh, was benched at halftime after completing four of 11 passes for 46 yards and two interceptions.

Neil O’Donnell, not expected to play because of elbow tendinitis, replaced Tomczak and directed scoring drives on his first two possessions. Foster’s five-yard touchdown run and two field goals by Gary Anderson made the score 17-13 with 2:34 left in the third quarter.

O’Donnell completed nine of 16 passes for 92 yards and Foster had 80 yards in 17 carries.

The 49ers, despite having only one holdover defensive line starter, sacked Tomczak and O’Donnell five times.