ENGLEWOOD, Colo. — It was the morning after the Broncos played their preseason game against the Seattle Seahawks when running back Theo Riddick approached the team’s medical staff.

Something’s not quite right with the shoulder, doc.

Tests revealed Riddick, who the Broncos signed as a free agent the week before, suffered a slight shoulder fracture against the Seahawks on Thursday night and will be sidelined six to eight weeks, league sources told 9News.

The good news is that Riddick’s injury will not require surgery to repair. And while it does mean Riddick will miss the first two to four games of the regular season, the Broncos already have an experience third-down back in place in Devontae Booker.

Riddick played six previous years with the Detroit Lions, averaging better than 61 catches in his past four seasons. He was waived two weeks ago by the Lions and after drawing interest from multiple teams, Riddick signed a one-year, $2.5 million contract with the Broncos. His deal has a full guarantee of $1 million.

Injuries are starting to hit the Broncos a little harder. The team lost inside linebacker/special teams standout Joe Jones for several weeks after he suffered partially torn triceps in the Broncos’ Hall of Fame game August 8 against the Atlanta Falcons in Canton, Ohio.

Starting fullback Andy Janovich is out six to eight weeks after he suffered a partially torn pec muscle injury Thursday in Seattle.

And now Riddick will join Janovich on the running back inactive list for at least the first two regular-season games on September 9 at Oakland and September 15 at home against the Chicago Bears.

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