ENGLEWOOD, Colo. (AP) — With Peyton Manning out until at least mid-December, the Denver Broncos have bolstered their depth at quarterback by signing Christian Ponder.

The former Minnesota Vikings first-rounder will serve as the Broncos’ third QB behind starter Brock Osweiler and Trevor Siemian.

Osweiler won his first NFL start last week at Chicago and Manning was fitted for a walking cast on his left foot after consulting with foot specialist Dr. Robert Anderson this week.

The Vikings drafted Ponder with the 12th overall pick in 2011. He started 36 games for Minnesota but struggled to live up to expectations, throwing 38 TD passes and 36 interceptions while completing only 59.8 percent of his passes.

Ponder signed with Oakland in March but didn’t survive final cuts.