Pittsburgh ? Jerome Bettis needs 66 yards to move into 10th on the NFL’s career rushing list. To Bettis, though, there is only one man ahead of him: John Riggins.

When the Pittsburgh Steelers’ running back gets to No. 10, he will surpass Riggins as the leading rusher among big backs – the power runners who pound out yardage, rather than accumulating it with bursts of speed and acceleration.

The 255-pound Bettis passed one of those glamour runners, O.J. Simpson, with 79 yards against Cincinnati on Sunday in his first meaningful playing time since injuring a knee five weeks before.

Bettis has 11,287 yards in 10 seasons, one of only three runners among the top 11 who played so few seasons. No. 6 Jim Brown played nine seasons, and No. 3 Barry Sanders played 10.

Because of the way he gains yardage, and the relatively short shelf life for runners who take the physical punishment he does, Bettis probably doesn’t have enough seasons left in him to overtake many more rushers. He has missed significant portions of this season and last with major injuries, something he avoided during his first nine NFL seasons.

Once he matches Riggins, Bettis would need 723 yards to surpass No. 9 Thurman Thomas and 1,388 yards to also get by Franco Harris, Marcus Allen, and Tony Dorsett to move into fifth place behind Emmitt Smith, Walter Payton, Sanders and Eric Dickerson.

To Bettis, outgaining Riggins – who played 14 seasons for the New York Jets and Washington Redskins :quot; was something he never envisioned when he left Notre Dame in 1993, certain he would be a blocking block in the NFL.

“He was a big back and when you look at big backs, that’s one you circle,” Bettis said. “He had the biggest production, so he’s the guy. To get past him, that definitely would be an accomplishment.

“As a big man, it’s hard to get the longevity to be able to get those numbers. He had durability and was always there to get the tough yards.”

Pittsburgh running back Jerome Bettis looks for running room in a game last season against Tennessee. Bettis needs 66 yards to move into 10th place on the NFL's career rushing list.

One thing Riggins accomplished was winning the 1983 Super Bowl with the Redskins. Bettis arrived in Pittsburgh the year after the Steelers last appeared in the Super Bowl, and he has twice played in the AFC championship game.

Bettis is fighting the perception his best years are far behind him. Slowed by injuries, he has only two 100-yard games in the last calendar year, both against Cincinnati this season.

At age 30, this will almost certainly be the first time in his seven seasons with the Steelers that Bettis does not gain 1,000 yards; he needs 589 in his last five games. He has failed to gain 1,000 only once, during his third and final Rams season, 1995.

Bettis would understand being written off if he were playing weekly and not gaining the yardage he once did. But when he’s been healthy the last two seasons, the yardage has come.

“People raise questions, but why?” he said. “Because I’m hurt? If you raise questions, I can understand it if the play has suffered, if it doesn’t look like he’s sharp, if he’s not hitting the holes. But people saying, ‘He’s getting injured more?'”

Until being sidelined by a groin injury with a month left in the regular season a year ago, Bettis was on pace for his best career season and was only a few yards off the NFL rushing lead.

“I can understand it if I kept getting nicked up, or injured a hamstring but it’s my knee,” he said. “People are saying that Jerome Bettis is washed up and he’s done and he should move on. But I’ve been hurt, so I don’t understand that.”