Peyton Manning has a partially torn plantar fascia in his left foot.

Manning had difficulty walking last week, according to some of his teammates.

Manning has battled plantar fasciitis for weeks but is believed to have aggravated the injury against Indianapolis on Nov. 8, resulting in a partial tear of his plantar fascia.

It is unclear how long Manning may be out.

"If [Manning's] healthy and ready to go, Peyton is our quarterback," Gary Kubiak said Sunday when asked about Brock Osweiler.

Manning won't start on Sunday as he works on getting back to full health.