Carswell had the accident on his way to the Broncos' facilities at about 7:10 a.m. Thursday morning. He suffered a ruptured spleen, a ruptured diaphragm, multiple rib fractures and a contusion of his entire left internal cavity.
His prognosis was "very good" after surgery Thursday, according to the Broncos. Carswell is done for the rest of the season and at age 33 his long-term future in football is in question.
Carswell is in his 12th season with the Broncos. Only kicker Jason Elam, who was drafted by Denver in 1993, has been with the team longer.
"Anytime somebody has an injury like that, such a freak accident, you don't know what to do," Broncos coach Mike Shanahan said. "You're just hoping that he's all right."
Carswell switched from tight end to the offensive line this season. He was a backup but played as an extra tight end in short-yardage situations. Carswell caught two touchdown passes against Jacksonville earlier this season on lineman-eligible plays.
The Broncos tried to maintain their focus on Thursday as they went through their usual practice while their teammate was in the hospital.
"You do have to work but obviously our minds are on that," fullback Kyle Johnson said.
PLAYER NOTES --CB Champ Bailey said he's not 100 percent yet, but he'll be matched up against Philadelphia WR Terrell Owens on Sunday. Bailey was penalized three times against Giants WR Plaxico Burress last week but said he doesn't mind facing physical receivers like Burress or Owens.
--CB Lenny Walls didn't practice again on Thursday because of a groin injury. He would have to make a quick recovery to be able to play on Sunday.
--S Sam Brandon still hasn't returned to practice after suffering a partial tear in his pectoral muscle. He is still hoping to be back for Denver's game after the bye, which is next week.
--QB Jake Plummer will have to be aware of Philadelphia's many blitzes on Sunday. Plummer has done a good job avoiding mistakes this season but he should be pressured this week.
--OL Chris Myers could become Denver's primary backup at guard now that Dwayne Carswell is out for the season. Myers is a rookie who played every position on the line in college.
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