Middle linebacker Brian Urlacher is expected to miss at least the next three games and possibly the remainder of the regular season with a strained right hamstring suffered in overtime during Sunday's loss to the Seattle Seahawks.
Urlacher, a 13-year veteran and eight-time Pro Bowl selection, leads the Bears with 88 tackles, is tied for the team lead with 7 tackles for lost yardage and has 2 forced fumbles and 2 recovered fumbles.
If the Bears (8-4) qualify for the playoffs, Urlacher could return for the postseason after suffering what was first clarified Tuesday by the Chicago Tribune as a Grade 2 hamstring strain.
But it's also possible he has played his last game as a Bear. Urlacher, 34, is in the final year of a five-year, $40.6 million contract.
He has expressed a desire to continue his Hall of Fame career, but a sprained knee in the 2011 season finale kept him out of this year's off-season program, training camp and the preseason and necessitated multiple medical procedures.
The former first-round pick from New Mexico had started all 16 games in six of the previous seven seasons.
Without Urlacher, strongside linebacker Nick Roach will move over to play in the middle, as he did vs. Seattle, with Geno Hayes filling in at strongside linebacker.
The 6-foot-1, 234-pound Roach has started 55 NFL games, 52 at strongside linebacker, including 10 of 12 this year (the Bears opened in nickel twice) and 15 last season.
The 6-1, 226-pound Hayes, a five-year veteran, started 42 NFL games at weakside linebacker with Tampa Bay over the past three seasons before signing with the Bears as an unrestricted free agent in the off-season.
When Urlacher suffered a season-ending dislocated wrist in the 2009 season opener, the Bears went on to finish 7-9, their only losing season in the previous four. The defense also allowed 375 points, more than they have permitted in 10 seasons.
Roach started three games in the middle in '09 with Urlacher out, although strongside starter Hunter Hillenmeyer spent most of the season in the middle, with Roach taking Hillenmeyer's previous spot.
The Bears also have lost backup linebacker Patrick Trahan, who was waived/injured after playing just one game. He was promoted last week from the practice squad.
To replenish their depth at linebacker, the Bears re-signed Dom DeCicco, who spent the 2011 season with the team and was second in special-teams tackles with 17.
Originally signed by the Bears as an undrafted free agent out of Pittsburgh, the 6-4, 230-pound DeCicco was released just before the start of the regular season after suffering a hamstring injury.
Fullback Harvey Unga was re-signed to the practice squad Tuesday, replacing quarterback Matt Blanchard, whose practice-squad contract was terminated.