FOXBOROUGH, Mass. (AP) – Chad Brown was once one of the NFL’s best linebackers.

He played in three Pro Bowls, had 13 sacks one year with Pittsburgh and led Seattle in total tackles during his eight years there.

He joined the New England Patriots last year and wasn’t the same player.

He struggled with the shift from outside to inside linebacker and started only five games. In one five-game stretch, he didn’t record a single tackle. And after starting the season as the sack leader among active linebackers with 78, he didn’t get even one.

So when coach Bill Belichick said at the final team meeting last season that veterans who were uncertain about their futures should delay a decision for a few weeks, Brown didn’t need the extra time.

He decided not to return.

But on Sunday, he was running around the field again on a hot summer day. He re-signed with New England last Thursday and has practiced every day since training camp began on Friday.

What changed?

“You start working out and you feel good, and you see a couple of NFL Network games and I realized I love the game,” Brown said. “I’m healthy. I feel great. Why not come out and do this again?”

He appears in excellent shape with a trim waist and flat stomach. His listed weight of 245 pounds seems inflated.

Brown started all 147 games in which he played in his 11 seasons before joining the Patriots. At 36, he knows he can’t play as well as he once did.

“Time waits for no man,” he said. “You get a little older. You get a little slower. You can’t recover at the same tempo as you once did. So you know that’s happening. Your ego attempts to deny it, but I try to deal in reality.”

So he’s “made peace” with his transition from a star to a backup at a number of positions. Last year he lined up at outside and inside linebacker and defensive end.

“We’ll try to use him in the way that most benefits the team,” Belichick said. “One of the advantages that he has is that he can do a number of different things for us.”

Brown started five of the first six games last season before inside linebacker Tedy Bruschi returned from a stroke and played the seventh game. Brown was inactive for that and made just eight tackles over the next eight games.

But in the regular-season finale against Miami, he played at outside linebacker and made eight tackles.

“I would like to, in a sense, re-establish myself,” Brown said. “I didn’t perform as I would have liked to and, my second year in the system here, having played all the different spots, I feel it will be much easier for me.”

He and the Patriots kept in touch after the season. He also spoke with other teams. But Brown, who lives in Colorado during the offseason, has a 9-year-old daughter and a 7-year-old son and had to consider whether moving them again made sense.

“Once I got them on board it became a no-brainer for me,” Brown said. “I knew I was going to be on a team and I was hoping it was going to be this one.”

Meanwhile, he worked out on his own.

“When you come to training camp there’s no half speed,” Brown said. “So I prepared fully as if I were under contract and now I am.”

His life is different now. He is playing catchup since he missed offseason meetings. He has gone from star to spare part. His skills have diminished with age.

But his love for the game remains strong. It’s the reason he was on the field Sunday with rookie linebackers who were 9 years old when he began his NFL career.

“I haven’t missed a year of football since I was 6. I’ve never really had a job for other than a couple of weeks in the summer other than football,” Brown said.