With Ben Roethlisberger’s shoulder sore and Antonio Brown “not looking good” to play after sustaining a concussion, the Pittsburgh Steelers (11-6) face a significant uphill battle against Peyton Manning and the Denver Broncos’ (12-4) top ranked defense in Sunday’s AFC Divisional Round playoff at Sports Authority Field at Mile High.

The quarterback Roethlisberger and his top receiver Brown were each jarred by rough tackles from Bengals linebacker Vontaze Burfict late in Pittsburgh’s 18-16 comeback victory over rival Cincinnati in last week’s Wild Card round. According to ESPN, Roethlisberger is “likely” to play against the Broncos No. 1 pass rush and top overall defense but Brown is still in the NFL’s concussion protocol and must pass it before the Steelers rule on his game status.

Roethlisberger, who is reportedly dealing with a sprained AC join in his throwing shoulder and has gone 1-1 in two career postseason games against Denver, still has receivers Martavis Bryant and Markus Wheaton to carve up the Broncos equally banged up secondary but replacing Brown is all but impossible.

Leading the NFL in receptions and garnering first-team All-Pro honors for the second straight year, Brown racked up a career-best 1,834 yards and 10 touchdowns in 16 games this season and stood out with 119 yards off seven receptions against the Bengals.

It was the threat of Brown’s playmaking down field that allowed Pittsburgh to overcome the loss of leading running back DeAngelo Williams to an injured foot, and helped Jordan Todman and Fitzgerald Toussaint tally 123 of the Steelers 167 rushing yards versus Cincinnati.

Now it’s also possible Williams will sit out again with NFL Network reporting he visited a specialist on Monday, which could mean more work for Todman and Toussaint. Both looked impressive but the second-year back Toussaint was especially helpful in the passing game with four receptions for 60 yards.

Whomever owns the Steelers backfield, however, will have to contend with a Denver defense that ranked third against the run, letting up a mere 3.3 yards per carry, and that expects defensive end DeMarcus Ware to play after he suffered a knee injury in the final game of the regular season.

Ware, who’s 7.5 sacks puts him behind only team leader and linebacker Von Miller’s 11.0 sacks on the year, sat out all of last week’s practice sessions. The Broncos are also dealing with the bruised shoulder of second-team All-Pro cornerback Chris Harris and safety T.J. Ward’s ankle knock and safety Darian Stewart’s hamstring injury.

Yet the Broncos hopes of second Super Bowl run in three seasons will hinge completely on health and overall play of Manning. The 39-year-old was hampered by foot and rib injuries this season and sat out six total games before coming back to lead Denver to a 27-20 Week 17 victory over San Diego to clinch the AFC’s No. 1 seed.

Manning led the Broncos on four successful scoring drives, though he did not register a passing touchdown. He was on pace for his worst completion percentage and interception total of his career before injuries set in, and Pittsburgh’s secondary and pass rush does present a significant challenge to Manning.

The Steelers were near the bottom of the league in passing yards allowed this season, but they finished tied for seventh with 17 interceptions forced and owned the third-best pass rush with 48 total sacks.

Betting Odds: Denver -6.5

Over/Under: 41 points

Prediction: Denver over Pittsburgh, 24-23