Welker took a hit to the head on a play across the middle late in the second quarter, and his neck bent awkwardly on the play. Welker previously suffered a concussion in Week 11 against the Kansas City Chiefs.
Earlier in the game, Welker caught his 10th touchdown pass of the season, leaving the Broncos as the only team in NFL history to boast four players with double-digit touchdowns. If fellow wide receiver Eric Decker can find the end zone three more times, Denver will have five players in double figures.
Denver likely will counter with more two-tight end sets, which should mean more playing time for Jacob Tamme.
Here are the rest of the injury updates from around the league:
1. NFL Media's Albert Breer reports that New England Patriots tight end Rob Gronkowski is believed to have suffered a torn right ACL during Sunday's win over the Cleveland Browns. An MRI to confirm the diagnosis is scheduled for Monday. It's a huge blow to the Patriots' Super Bowl aspirations, as Gronkowski is in the conversation for most valuable non-quarterback in the NFL.
2. Minnesota Vikings running back Adrian Peterson was carted off the field with what NFL Media Insider Ian Rapoport labeled a right mid-foot sprain. The Vikings, who fell to the Baltimore Ravens on Sunday, have to be holding out hope that it's not a dreaded Lisfranc injury.
3. Defensive Rookie of the Year candidate Tyrann Mathieu's season is over after collapsing on the field during the Arizona Cardinals' victory Sunday over the St. Louis Rams. The Cardinals believe Mathieu has a torn ACL in his left knee.
4. The Detroit Lions held running back Reggie Bush out of Sunday's loss to the Philadelphia Eagles after the running back appeared to aggravate his calf injury in warmups. Fellow running back Joique Bell totaled 127 yards from scrimmage in Bush's absence.
5. Seattle Seahawks coach Pete Carroll confirmed that weakside linebacker K.J. Wright broke a bone in his foot during Sunday's defeat to the San Francisco 49ers and likely will be sidelined six weeks. Wright has been one of the best coverage linebackers in the league, but the deep Seahawks have a quality replacement in Malcolm Smith.
6. Miami Dolphins running back Lamar Miller missed the second half of Sunday's triumph over the Pittsburgh Steelers after sustaining a concussion. Backup Daniel Thomas rushed for a season-high 105 yards in his absence.
7. Detroit Lions defensive end Ziggy Ansah left Sunday's loss to Philadelphia with a shoulder injury and did not return.