LAKE FOREST, Ill. — Chicago Bears head coach Ben Johnson announced Tuesday that safety Coby Bryant will miss 4-6 months after undergoing surgery on his knee.That timeline will take him out for most if not all of the regular season, and it’s longer than the previously-reported 8-10 weeks.“This was what I have been told all along,” Johnson said. “We were getting opinions on it, so it’s four to six months is what I have been told.”Coby Bryant injury a 'disaster' for Chicago BearsRobert MaysThe Bears’ prize of free agency, Bryant signed a three-year, $40 million contract in March. In his limited time with the team, he had already impressed the Bears both on and off the field. He made an outstanding interception earlier in camp, while his teammates and coaches have raved about his work habits and leadership.“I love his play style,” defensive coordinator Dennis Allen said last month. “I think it epitomizes the way we want to play the game.”First-round rookie Dillon Thieneman is the other starting safety, and a major plus of having a Super Bowl-winning safety like Bryant was to help Thieneman grow. Now, that challenge will fall to a different player.Free agent acquisition Cam Lewis has gotten the first crack at replacing Bryant. The versatile defensive back moved from nickel to safety before he had to leave practice with an injury. Then it was veteran Xavier Woods, who has 121 starts in his career, including 10 last season for the Titans when he had two picks. Woods has 15 career interceptions and began his career in Dallas with Bears secondary coach Al Harris.