PITTSBURGH (AP) _ This is how it was supposed to be in January for the Pittsburgh Steelers.

Forcing turnovers rather than committing them, Pittsburgh bolted to a 25-point first-half lead that even San Diego couldn't rally from and beat the Chargers 31-16 Sunday in a rematch of the AFC championship game.

The Steelers, the NFL leader in turnover ratio last season but last this season after making 11 in losses to Miami and Minnesota, pressured Stan Humphries into a career-high four interceptions _ two returned for touchdowns.

``They were playing the AFC championship game, and most of us knew it,'' the Chargers' Shawn Lee said. ``We rolled on this wave a little too long. Maybe we were a little overconfident.''

``No, they were a lot overconfident,'' said Willie Williams, who made his first two NFL interceptions. ``They thought they would come in here and roll over us.''

Williams and Alvoid Mays each returned an interception for a touchdown in the first quarter as the Steelers, refusing to wait for their oft-bumbling offense to score, revived their big-play Blitzburgh defense of last season.

``Revenge? We weren't looking for revenge, we were just looking to win no matter who we were playing,'' said Mays, who is replacing the injured Rod Woodson. ``I mean, we've been looking bad.''

Erric Pegram rushed for 95 yards in his first Steelers' start. And Mike Tomczak, despite not throwing for any touchdowns, was intercepted only once after committing six turnovers _ five interceptions and a fumble _ the previous two weeks.

``Maybe people were panicking around (Pittsburgh), but we're still a championship caliber team,'' said Tomczak, who like Mays and Williams is replacing an injured regular. ``The returns by the defense were fantastic. We got that good feeling back that we were missing.''

Humphries, whose unruffled style was a key to the Chargers' 17-13 AFC championship game upset, threw only three interceptions in four games only to become flustered by Pittsburgh's constant pressure.

``Their problem became our problem,'' Chargers coach Bobby Ross said. ``You don't win when you turn the ball over. When you make an interception and get a touchdown out of it, that's huge. You expect to get one of those a season, let alone two in a (quarter).''

Williams, constantly picked upon this season as he subs for the still-recuperating Deon Figures, made a 63-yard touchdown return with 6:10 left in the first quarter to put Pittsburgh up 14-0.

Mays followed with a 32-yard scoring return _ his first on any level of football _ to make it 21-0.

``Yeah, they were picking on me, but what do you expect? I'm replacing Rod Woodson,'' Mays said. ``If I were the quarterback, I'd pick on me, too. But the Steelers' defense is a dominating defense again, and we know we've got to take it away. That's our style.''

Pittsburgh (3-2) avoided its first three-game losing streak under coach Bill Cowher and now is 10-0 against San Diego (3-2) in regular-season games in Pittsburgh.

The Chargers' only two victories in Three Rivers Stadium were in the playoffs _ including last January.

Pegram's running led two scoring drives finished off by Bam Morris touchdowns and took the pressure off Tomczak to make big plays. Pittsburgh's early lead also neutralized the running of Natrone Means, who had 92 yards but failed to gain 100 for the first time in four games.

The Chargers also played most of the final three quarters without Pro Bowl linebacker Junior Seau, who reaggravated the strained right hamstring that limited him to eight tackles in his first two games.

The Steelers, unable to establish the run after falling behind early to Miami and Minnesota, drove 75 yards on the game's first possession for Morris' 1-yard touchdown run at 8:57 of the first. Morris was benched after gaining only 19 yards in the Steelers' 44-24 loss to Minnesota.

``We knew we needed to get the run going,'' said Pegram, a 1,000-yard back at Atlanta in 1993. ``That first drive was very, very big to give us an early lead and show we could get the job done.''

Humphries, harassed by Chad Brown and Greg Lloyd on nearly every first-half passing attempt, then threw a pass that deflected off Shannon Mitchell's hands directly to Williams, who broke three tackles on a circuitous route to the end zone. Both Humphries and Means missed tackles.

Mays' first interception also was deflected _ this one by tight end Alfred Pupunu.

Humphries, who was 22-of-40 for 257 yards, hit Tony Martin on a 19-yard touchdown catch that cut Pittsburgh's lead to 31-13.

But Williams intercepted Humphries again on San Diego's next possession, and the Chargers later settled for a John Carney field goal after Lloyd sacked Humphries on second-and-goal from the Steelers 3. A touchdown there would have cut Pittsburgh's lead to 10 points with nearly a quarter to play.