ENGLEWOOD, Colo. -- With Rahim Moore still recovering from surgery on his lower left leg, the Denver Broncos signed veteran safety Michael Huff on Tuesday.

To make room for Huff, Moore was moved to injured reserve, but designated to return so the Broncos can bring him back to the roster as soon as doctors clear him to play. Moore will be eligible to resume practicing with the Broncos on Dec. 31, after six weeks, so if he recovers from his injury he would be eligible to return for the postseason.

Safety Michael Huff, who played against Denver in Week 1 as a member of the Ravens, will join the Broncos. Doug Pensinger/Getty Images

Huff, a former first-round pick by the Oakland Raiders released by the Baltimore Ravens earlier this season, was one of three safeties to work out at the Broncos' Dove Valley complex Tuesday.

Moore is expected to miss some time after suffering what Broncos interim head coach Jack Del Rio said was "lateral compartment syndrome,'' often an impact injury that causes bleeding and swelling in the lower leg. Moore had left the Broncos' 27-17 victory over the Kansas City Chiefs in the first half and did not return.

Moore, some of his teammates have said, had been experiencing at least some discomfort in his leg in the days leading up to the game. After returning home following the game, Moore was still experiencing pain in his leg and called Broncos head trainer Steve Antonopulos, who arranged for Moore to be examined by the team's medical staff as quickly as possible.

Moore had surgery Monday morning and Del Rio has said he's uncertain what the timetable is for his return. Huff, who had signed a three-year, $6 million deal with the Ravens last March, struggled on the field in Baltimore and is expected to be a depth signing for the Broncos.

Mike Adams is expected to play in Moore's free safety spot and David Bruton plays in the Broncos' specialty packages as a third or fourth safety.

The Broncos also worked out John Boyett, who had been with the Colts, as well as former Giants safety Tyler Sash.