Welker didn't play in last week's loss to the Chargers, and he hasn't yet been medically cleared to return to practice.
Andre Caldwell, who has played sparingly this season but had six catches for 59 yards and two touchdowns against San Diego, is expected to replace Welker in the lineup.
"I thought Bubba Caldwell played really well," quarterback Peyton Manning said Wednesday. "Great route on that first touchdown, did a great job getting in the end zone on a play he hasn't [worked] that much, so that's a good job knowing what to do, being in his playbook. We'll count on him this week if he has to play."
Welker, 32, signed a two-year deal with the Broncos in the offseason. He has 73 receptions for 778 yards and 10 touchdowns this season, and he ranks 18th in WR efficiency, according to Football Outsiders.
The Broncos could choose to keep Welker out until the playoffs. By beating the Texans and Raiders to finish out the regular season, Denver would earn the AFC's top seed and a first-round bye, which would give Welker a month off between starts.