Rypien will be signed to the Rams' 53-man roster from their practice squad Thursday, Tom Pelissero of NFL Network reports.
Rypien will be the beneficiary of Stetson Bennett's placement on the reserve/non-football injury list, which took place Wednesday. The Boise State product will now operate as Matthew Stafford's backup beginning Sunday against the 49ers. The 27-year-old appeared in four games with the Broncos last season, completing 53 of 88 passes for 483 yards, two touchdowns and four interceptions.