Indianapolis Colts RB Donald Brown has been slowed by injuries all season, and now his season is over. (US Presswire)

Colts RB Donald Brown was expected to be the starting running back this season for the Indianapolis Colts, but injuries have derailed his season. Brown's season ended Tuesday when he and fullback Robert Hughes were placed on injured reserve. Veteran backs Mewelde Moore and Deji Karim have been brought on as replacements on the active roster.

Both Moore and Karim were with the Colts earlier this season, with Moore being waived at the end of October.

"The nice thing about it is Mewelde knows the offense and has been an excellent player in the month of December over his career so he can step right back in," interim coach Bruce Arians said Wednesday. "Deji was here for training camp, so he’s got a good handle on what he’s doing; it’s just getting back into football speed.”

Luckily for the Colts, rookie running back Vick Ballard has emerged as a solid option out of the backfield, but the offense will be devoid of a change-of-pace back -- a role Brown occupied. Still, this is an Indianapolis team that has not been primarily reliant on the run, so the loss of Brown doesn't figure to be a major factor.

And with Delone Carter injured, Arians indicated Wednesday that Moore will be first up to spell Ballard on Sunday.

Other injuries: Carter (ankle), center Samson Satele (ankle), safety Tom Zbikowski (knee), tackle Winston Justice (bicep) and linebacker Kavell Carter (hamstring) all missed practice Wednesday. Carter won't play, but Arians was hopeful that Zbikowski and Justice would be able to practice this week, at least.

Playoffs? As surprising as it seems now, the Colts can, in fact, miss the playoffs. It would take some doing, however. There are obviously several complicated scenarios, but if Indy wins one of its last three (at Houston, at Kansas City, vs. Houston), the Colts are in. Similarly surprising, the Colts, too, have a chance to win the division. It all starts Sunday at Houston. A win there, and they could sneak up to the top of the division. Texans can win the division with a victory over Indianapolis on Sunday.

For more up-to-the-minute news and analysis from Colts blogger Evan Hilbert, follow @CBSColts.