Welker returned to the practice field on Christmas Day for the first time since suffering his second concussion on Dec. 8, though it's highly unlikely the five-time Pro Bowler will suit up Sunday.
''It was good to see him out there,'' coach John Fox said.
Welker, who has missed the past two games, is third on the team with 73 catches and 778 yards to go along with 10 touchdowns. He also has 22 receptions for 311 yards while scoring in each of his last three meetings with the Raiders.
While the Broncos (12-3) were relieved to see Welker given clearance to practice, they won't see Miller again this season. The two-time Pro Bowl linebacker is out after suffering a torn ACL in his right knee in Sunday's 37-13 win at Houston that gave Denver its third straight division title.
Miller, who set a team record in 2012 with 18 1/2 sacks to go with 28 tackles for loss and six forced fumbles, finished with five sacks and 33 tackles this season after missing the first six games due to a drug suspension.
''It's definitely going to be a blow,'' executive vice president John Elway said on his weekly podcast on the team's website. ''But I think that we've done a good job of handling adversity throughout the year. This is another bump in the road for us.''
Although they've lost safety Rahim Moore (leg), defensive linemen Kevin Vickerson (hip) and Derek Wolfe (illness) and offensive lineman Ryan Clady (foot) to injury, the Broncos are in position to wrap up home-field advantage throughout the AFC playoffs with a win at Oakland (4-11).
Having Peyton Manning certainly has helped make up for those losses. The four-time MVP could be on his way to another award, leading the league with 5,211 yards and an NFL record 51 touchdown passes.
The 37-year-old Manning surpassed Tom Brady's mark of 50 TDs set in 2007 by completing 32 of 51 for 400 yards and four touchdowns against the Texans. He connected on a season-high 86.5 percent of his attempts (32 for 37) for 374 yards and three scores in a 37-21 win over visiting Oakland on Sept. 23.
Manning has won six in a row against the Raiders dating to his time in Indianapolis. Since joining the Broncos, he's completed 79.3 percent of his passes for an average of 340.7 yards with seven touchdowns and one interception in three meetings.
He'll try to continue that trend against an Oakland team that has given up a league-worst 33.6 points per game since Nov. 3.
Following a 26-13 loss at San Diego on Sunday, the Raiders are having to deal with more than just a five-game losing streak after Terrelle Pryor's agent accused the team of putting the quarterback in a position to fail by starting him this week.
Agent Jerome Stanley told CSN Bay Area he believed coach Dennis Allen hopes Pryor struggles Sunday to justify the decision to play Matt McGloin the past five weeks - even after Pryor recovered from a sprained knee.
Pryor, however, has since apologized on Twitter and in a conversation with Allen for the comments. The coach said he holds no ill will toward Pryor.
''This isn't the `Real Housewives of Beverly Hills,' this isn't made for TV drama,'' Allen said. ''This is football and we make our football decisions based solely on that, nothing other than that. I don't really give it a lot of thought. I can't control the ignorance that might come out of somebody else's mouth.''
Pryor completed 68.3 percent of his passes with four touchdowns and two interceptions in his first four starts, including victories in both the team's home games over that span. The third-year pro also went 19 of 28 for 281 yards and a score in the loss at Denver.
But he struggled in his last four starts, completing 50.8 percent of his attempts with one touchdown and eight picks before missing time with a sprained MCL. Pryor has been effective in the running game, totaling 527 yards on 7.1 per carry and two touchdowns in his 10 appearances.
''We had an opportunity to watch Matt McGloin for six games and now I want to get another opportunity to watch Terrelle go out there and play,'' Allen said. "I think we need something that's going to spark the football team and I think this can be something that can spark our team.''
The Raiders, who haven't beaten the Broncos at home since Dec. 19, 2010, will miss the playoffs for the 11th straight season.