FOXBORO, Mass. (AP) – Patriots linebacker Ted Johnson announced his retirement on Thursday, saying a series of concussions suffered over the course of his 10-year NFL career had made it unsafe for him to continue playing.

A member of three Super Bowl champion teams in New England, Johnson notified the team of his decision a day before veterans were scheduled to begin training camp.

With fellow inside linebacker Tedy Bruschi sitting out the season as he recovers from a mild stroke he suffered in February, the defending champions will be without two of their core defensive players.

“It is with deep regret that I have decided to retire from football,” Johnson said in a statement issued by the team. “The decision was not an easy one, but life sometimes has a timetable all its own. I can no longer ignore the severe short- and long-term complications of the concussive head injuries I have sustained over the years.”

Johnson, 32, was drafted by the Patriots in the second round of the 1995 NFL Draft out of Colorado, the 57th overall player selected. The 6-foot-4, 253-pound linebacker started 106 of 125 regular season games from 1995 through 2004 and was credited with 865 career tackles and 11 1/2 sacks.

“Ted informed me of his decision today and we had a good discussion,” Head Coach Bill Belichick said. “Although his retirement is unexpected, we thoroughly respect his decision and support him as he moves on.

“It goes without saying, but Ted Johnson is a class act,” he said. “He was a solid contributor to this defense and the New England Patriots organization his entire career. Ted’s signature was a work ethic and toughness that were second to none. He retires a champion.”

One of the team’s best run-stoppers, Johnson missed half of the 2003 season with a broken foot. But he came back to start 15 of 16 games last year and finished third on the team with 112 tackles, including a sack. His 15 starts were his most since 1997.

“I am proud of all that Ted Johnson has done for the Patriots, both on the field and in the community,” Patriots owner Robert Kraft said. “I know that he positively impacted the lives of thousands of Patriots fans and I fully expect that he will continue to be a positive role model in our community.”

Johnson had been one of the few Patriots left from the 1996 team that lost to Green Bay in Super Bowl XXX1.

The losses of Johnson and Bruschi leaves New England without either of its starting inside linebackers from last season. The Patriots signed free agents Monty Beisel and Chad Brown during the offseason to provide depth at the position.

New England has 16 linebackers on its 85-player roster – including returning starters Willie McGinest, Mike Vrabel and Rosevelt Colvin – heading into training camp, which starts Friday.

AP-ES-07-28-05 1201EDT