"Brock's our quarterback -- nothing has changed from that standpoint," Kubiak said, via the team's official Twitter account. "(Manning) being available is a change."
Kubiak emphasized that it's time for Manning to "take the next step" because the veteran quarterback appears healthier than he has been since the team revealed his plantar fascia tear in mid-November.
"He's throwing the ball well," Kubiak added. "Last week was a very positive sign."
Although Kubiak has expressed outward confidence in Osweiler, he acknowledged that Manning's availability is "a great thing for this football team."
Manning spoke to reporters a short time later about his role this week as he tries to complete his comeback.
"I will do what I can to help Brock and the team," he said.
Is that a tacit admission that Manning could reclaim the starting job if Osweiler stumbles versus the Chargers? Or merely relief at the prospect of a veteran insurance policy should Osweiler go down with a serious injury?
In an ideal world, Kubiak won't have to address those questions entering the postseason.