Starting defensive tackle Marcus Thomas will miss the remainder of the preseason with a strained pectoral muscle. Thomas' chest muscle wasn't completely torn off the bone, as Elvis Dumervil's was when he suffered a season-ending injury early in last summer's training camp, so the Broncos hope he'll be ready for their Sept. 12 season opener against the Oakland Raiders.
The news could be worse for fellow defensive tackle Ty Warren, who suffered a torn triceps that could threaten not only his season but his career. The Broncos hope Warren, who signed a two-year, $8 million contract this year, won't need surgery and can return to the field at some point this season. However, that would mean going one man down on the roster for a while.
Thomas and Warren were injured within five minutes of each other Monday when they lined up with the first-team defense during a 9-on-7 drill.
Thomas was starting in both the Broncos' base and nickel defenses, and Warren was their biggest, most accomplished defensive tackle in the rotation.
"Those are two vital pieces that were going to be a part of this defense," Vickerson said. "We can't think about it. We've just got to keep on keeping on, and the next guy has got to be ready. That's why you can't have any weaknesses in your depth chart and you can't have anybody getting lax."
"I knew he was fired up and showed a lot of emotion because he got back on the field after a year off," Vickerson said. "I know it's kind of messing with him a little bit just because he's going through an injury like this, but hopefully it's not a season-ending injury and he can come back soon."
In other news, the Broncos released running back LenDale White. The former USC star never had the chance to play for his hometown team. He suffered a torn Achilles tendon in the preseason finale last year and missed the entire season.
White ran for 10 yards on four carries in the Broncos' preseason opener this year, but he hadn't been on the practice field enough to compete for a roster spot.
"It's just a tough injury for any NFL player to overcome, especially at running back, through a lockout. We couldn't supervise anything," Broncos general manager Brian Xanders said.
White's chances also were hurt when back spasms sidelined him for several days early in camp.
"We want all of our guys to compete 100 percent during practice," Xanders said.
Notes: The Broncos claimed LB Alvin Bowen off waivers and released LB A.J. Jones. ... TE Richard Quinn (knee), OL Stanley Daniels (ankle) and DB Syd'Quan Thompson (groin) didn't practice, and WR Eric Decker (foot) and DT Ronnell Brown (unspecified) didn't complete practice. Decker said his left foot, which was surgically repaired 18 months ago, was sore, and he was just being cautious. He said he'll be back Wednesday.
The Associated Press contributed to this report.