The news broke in the third quarter of Sunday night's game between the Bears and Broncos and was later reported on NBC's ProFootballTalk.com.
The Web site speculates that the team may have suggested Bruschi should retire, though at this point, it is just that — speculation. His Monday announcement could clear things up.
The Patriots sent out a note late Sunday evening announcing a news conference "for an important player announcement at 10:45 Monday morning, August 31, in the media workroom at Gillette Stadium."
Bruschi had hinted earlier in the week that his role had yet to take form.
"I've had so many years where, where you are in September is different from where you are in December," Bruschi told The Boston Globe on Tuesday. "So I've learned that, ever since I was a third-down situational pass-rushing rookie that played on special teams, all the way through my entire career, that you never assume what your role is going to be. Just be ready when your coach calls on you."
Bruschi played 13 seasons for the Patriots, playing in 189 regular-season games and five Super Bowls, winning three of them. He's compiled more than 1,000 tackles, including 30 1/2 sacks. He's made 12 interceptions and has scored four touchdowns on defense.
He will go down as one of the most memorable Patriots of all time. He was a major part of the three Super Bowl victories before suffering and returning from a stroke in 2005. He was forced to miss the final three games of the 2008 regular season due to a leg injury. He recorded one solo tackle in Friday's preseason game against the Redskins.