PHILADELPHIA -- In Philadelphia, Patrick Chung was part of the problem. In New England, the veteran safety is evidently part of the solution.

The Patriots signed Chung, 27, to a new three-year contract extension, according to ESPN's Field Yates. Chung will make $3.4 million guaranteed and up to $8.2 million over the three seasons.

Two years ago, the Eagles signed Chung as a free agent. He left the Patriots for a three-year, $10-million contract that was part of the Eagles’ overhaul of their secondary. The team also signed cornerbacks Cary Williams and Bradley Fletcher during that offseason.

Fletcher, Williams and Nate Allen were all back with the Eagles in 2014. Chung was out. It was hard not to interpret his release after one season as a sign that Chung was a big part of the Eagles’ problems in 2013. Their secondary led the NFL in touchdown passes allowed.

A year later, Chung has a new deal with the Patriots. He got his career back on track, starting in a Patriots secondary that was ranked 17th overall against the pass. Without him, the Eagles were ranked 31st in pass defense.

The lesson is that, in a team sport like football, the same player can look very good or very bad depending upon the players around him. In New England, Chung plays alongside safety Devin McCourty. The cornerbacks he has to help out are Darrelle Revis and Brandon Browner. With talent like that around him, Chung played very well in 2014. He was credited with 89 tackles (third on the Patriots), seven passes defensed and one interception.

After watching Chung struggle with the Eagles -- on the field, of course, but also in the locker room, where he never seemed comfortable -- it would have been tough to imagine him thriving on a good team. That may say more about the environment in Philadelphia than anything else.

“Pat and I talked about that,” Patriots coach Bill Belichick said during the season, according to ESPN’s Mike Reiss. “We had a long conversation about a lot of things. I don't think it was anybody's fault. It was just one of those things that didn't work out. We both felt that we would want to try to give it another shot, and we were able to come to an agreement on that contractually, and I think he has done a real good job for us. He's filled a lot of different roles. He's played well, helped us in the kicking game, helped us defensively in a number of areas. He's been around the ball, productive."

Replacing Chung with Malcolm Jenkins was one of the Eagles’ key moves last offseason. It paid dividends, too, as Jenkins helped settle down the rest of the secondary. But Fletcher and Allen are eligible for free agency this offseason. Chances are, the Eagles will use that as an opportunity to upgrade a secondary that has been a problem area for the past three years.

This time, they will not be able to sign Chung.