ATLANTA -- For the second time in a week, the Atlanta Falcons have lost a key defensive starter to an offseason injury that could sideline him several months. This time, it's standout tackle Rod Coleman, who suffered a ruptured right quadriceps that required surgery Monday.
The team's starting "under" tackle and a Pro Bowl-caliber defender, Coleman will likely miss the entire offseason training program and training camp and there is a chance he might not be completely rehabilitated by the start of the regular season.
The injury, which Coleman acknowledged to several teammates, occurred over the weekend in a boating accident.
Starting weakside linebacker Demorrio Williams last week suffered a torn pectoral muscle while lifting weights, general manager Rich McKay revealed Sunday, and his rehabilitation timetable is five months. The loss of Williams, a fourth-year veteran and one of the team's best athletes, precipitated the selection of South Florida outside linebacker Stephen Nicholas in the weekend's draft.
First-year coach Bobby Petrino said Nicholas, chosen in the fourth round, will line up with the starting unit when the Falcons convene for a mandatory minicamp late next week.
Coleman, 30, may be extremely difficult to replace. The eight-year veteran is one of the premier interior pass-rushers in the NFL and leads the league in sacks by a tackle (44½) over the past five seasons. Noted for his quickness and ability to penetrate through the inside gaps, Coleman possesses a rare skills-set.
Since joining the Falcons as an unrestricted free agent in 2004, Coleman has 28 sacks in 44 games, including 11½ in 2004 and 10½ in 2005. He earned a Pro Bowl berth in 2005.
The former East Carolina star, chosen by Oakland in the fifth round in 1999, played the first five seasons of his career with the Raiders before departing in free agency. For his career, Coleman has 281 tackles, 56½ sacks, nine forced fumbles, three recoveries, one interception and 26 pass deflections. He had played in 104 games and started 65 of them.
Like most teams, Atlanta is not deep at the tackle position, and the loss of Coleman, even if only for the offseason program, is a major setback as new coordinator Mike Zimmer tries to revamp a defense that statistically ranked 22nd in the league in 2006. The only other proven veterans on the team are Grady Jackson and Jonathan Babineaux and Darrell Shropshire.
Compounding the situation is that Jackson is upset over his contract, has not participated to date in the offseason program and is suing the team for defamation and invasion of privacy. Jackson, who has two years remaining on his contract, alleged in the suit that club officials divulged information about a physical examination that he took when Atlanta was courting him as a free agent last spring.
It is not known if Jackson, a 10-year veteran whose forte is anchoring against the run, plans to attend the mandatory minicamp next week.
The Falcons have entertained at least three veteran tackles during the unrestricted period -- Ian Scott (Chicago), Seth Payne (Houston) and Kenderick Allen (Green Bay) -- but have yet to sign a veteran of consequence. Atlanta did claim two-year veteran Anthony Bryant on waivers from Detroit last month and on Sunday chose Trey Lewis of Division II Washburn in the sixth round of the draft.
Len Pasquarelli is a senior writer for ESPN.com.