Brock Osweiler will be Denver's starting quarterback Monday night.
The Broncos host the Cincinnati Bengals in Week 16.
Peyton Manning is not expected to practice Wednesday or be active this week, according to the Broncos' website.
Manning is recovering from a torn plantar fascia. He was cleared to practice last Wednesday and Thursday before suffering a setback Friday.
— Broncos TV (@BroncosTV) December 23, 2015
The decision to have Osweiler start Monday came after conversations Head Coach Gary Kubiak had with Manning earlier this week, said Andrew Mason, Senior Digital Reporter for the Broncos.
"Improving the performance of the entire offense in the second half will be a priority this week," Mason said.
Osweiler's performance has fallen sharply during the second half.
"He has a sizzling 109.4 first-half rating, but his second-half rating is 44 points lower," Mason said. "His sack rate also spikes in the second half, rising from one every 19.8 dropbacks to one every 9.5 dropbacks."