Former Pro Bowl safety Bob Sanders, a key to last season's dramatic playoff turnaround for the Indianapolis Colts defense, practiced yesterday for the first time since having offseason surgery on his left shoulder.

Sanders had been on the physically unable to perform list since the Colts opened training camp and had been limited to conditioning work.

"I feel strong, I feel fast, and I'm ready to go," Sanders said before yesterday's workout.

Sanders is the Colts' biggest hitter and teammates credit him with bringing a more aggressive attitude to the defense, a difference that helped revitalize the team's defense during the 2006 playoffs.

He started only four games in the regular season when the Colts ranked last in the league against the run. When Sanders returned in the postseason, the Colts responded by limiting Kansas City's Larry Johnson to 32 yards on 13 carries and held Baltimore without a touchdown.

"He's a big part of this defense," three-time Pro Bowl defensive end Dwight Freeney said. "We saw him for only four games last year, and he brings a lot to this defense. He really does make a difference."

For three weeks Sanders said he felt good enough to play but acknowledged coaches and doctors were being cautious about letting him hit too soon or too often.

"I think, actually, we've overdone it as far as the time I could have come back," Sanders said last week. "But the extra time did help me get stronger."

Sanders will still face some limitations. He is expected to play in Saturday night's preseason game against Detroit, though coach Tony Dungy was unsure whether Sanders would play into the third quarter like most of the starters usually do for the third exhibition game.

"He brings an energy and a physicality that we really like," Dungy said. "He probably will be on a play count, but I don't know what that is yet. We'll see how he gets through practice this week, but it's probably not going to be 35 or 40 plays."

Even without Sanders in the lineup, the Colts' defense has looked more aggressive during the preseason.

The new starting cornerbacks, Marlin Jackson and Kelvin Hayden, tackled well in Monday night's 27-24 loss to the Bears. The team's front seven also consistently pressured Chicago quarterback Rex Grossman, who helped the Colts look even better by fumbling three times, throwing an interception and taking a sack in 26 plays.

Still, Sanders' return was welcome news for a defense that has already lost four starters from its Super Bowl lineup — linebacker Cato June, defensive tackle Anthony McFarland and cornerbacks Jason David and Nick Harper.