PITTSBURGH, SEPT. 14 -- Coach Chuck Noll of the Pittsburgh Steelers wrote a letter to his players this summer, telling them it was time to return to the physical, blue-collar style of steel town-tough football of a decade ago.

The Steelers were letter-perfect in carrying out those instructions Sunday, burying the favored San Francisco 49ers, 30-17, in a game linebacker Mike Merriweather said marked the return of "old-fashioned Steelers football."

"We played the style of play that Chuck Noll wants us to play . . . tough, physical, everybody to the ball, make the big plays," Merriweather said. "We'd been getting away from that."

The Steelers didn't need trick defenses in the days of Joe Greene and Jack Lambert and Jack Ham, but they had experimented in recent seasons with gadget defenses that included a variation of the Chicago Bears' "46" defense and a five-linebacker alignment called "The Press."

They threw out all the gimmicks against Joe Montana and the 49ers' sophisticated, high percentage-passing offense.

Instead, they concentrated on taking away the deep pass from quarterback Montana, forcing him to throw dump off passes to his running backs, and gang-tackled the 49ers' wideouts when they did catch the ball.

"We played a more physical defense and it was a big factor in the way the game turned out," Noll said today at his weekly news conference. "We have stressed that."

He said that, despite an 0-4 record in the exhibition season, "that was the one area we had improvement in. We didn't win the battle of the hitting last year in the preseason. This year I feel we hit with all of them."

The Steelers' defense got big plays from rookie cornerback Delton Hall and Merriweather. Merriweather's punishing tackle on Roger Craig forced the fumble that Hall returned for a 50-yard touchdown and a 7-0 lead. Each had an interception as the 49ers committed four turnovers.

"We forced them to play catch-up football, and that's a situation we haven't been in for a while," Noll said.

"It's a different game when you have to play catch-up. Defensively, it was an exceptional effort. The interceptions and fumbles were caused by the hard hitting, and they set it up for us offensively."

The Steelers' performance was a direct reversal of their 30-0 season-opening loss to Seattle last year, except for the play of quarterback Mark Malone. He played poorly in each gane and against the 49ers completed only nine of 33 passes for 99 yards.

Malone, playing with a gash in his elbow that required postgame stitching, was booed loudly and often. "I didn't feel very good about that," Noll said.

"Knowledgeable people wouldn't have done it," Noll continued. "People get hung up with emotion more than anything else. Mark did a good job under the circumstances. You don't measure a quarterback's capabilities just by numbers . . . the bottom line is we won."

Several breakdowns in pass protection forced Malone to throw the ball away, but Noll was happy with his makeshift offensive line.

Starting tackles Ray Pinney and Tunch Ilkin were sidelined, forcing guard Craig Wolfley and recent waiver wire pickup Buddy Aydelette to start at tackle.

"I thought the whole offensive line did a good job of coming off the ball," Noll said. "If you had told me beforehand that we'd start the season with those guys at tackle, I'd have been surprised.

"Buddy doesn't have much experience with our system. The good thing is when we get everybody healthy, these guys getting experience under fire can only help."

The Steelers will play Sunday at AFC Central Division rival Cleveland, a 28-21 loser to the New Orleans Saints.

"This was one win," Noll said. "Now what you look for is improvement. You look for people to keep getting better. That's what we'll look for Sunday."