Because it wouldn't be December if the Pittsburgh Steelers weren't battling a swarm of injuries on the offensive line, we have this:
The team announced Tuesday that guard Willie Colon was placed on season-ending injured reserve with the knee injury he aggravated in a Week 14 loss to the San Diego Chargers. Removing Colon off the active roster paved the way for the arrival of running back Rashard Mendenhall, who returned to the team Monday following his one-game suspension.
It marks the third straight year Colon has been shipped to IR, but this time the Steelers have a plan. Rookie David DeCastro made his debut at right guard in Sunday's loss to the Dallas Cowboys with Ramon Foster slotted at left guard.
"I thought (DeCastro) did a nice job (with) very few, if any, mental errors," coach Mike Tomlin said Tuesday.
DeCastro and Foster might be a combination that sticks going forward if the Steelers aren't interested in paying Colon the $5.5 million he's due in 2013. The 29-year-old started 11 games this season, and is under contract through 2015, but his price tag remains steep for a player who can't seem to stay healthy.
Follow Marc Sessler on Twitter @MarcSesslerNFL.