This article is part of our Depth Chart Watch series.
After the previous week's series of injury disasters at running back, Week 12 started quietly – the 1 p.m. games passed without any sort of calamity. Things got worse from there, though, with Rob Gronkowski and Jimmy Graham both going down to knee injuries, a development that will land fantasy owners in a waiver-wire kerfuffle over tight ends. When you lose a guy like Gronk, there are no real answers. Graham has been an enormous disappointment, but that doesn't mean it's easy to replace him on the wire either. Let's see how their teams are dealing and what else is going on around the league.
Arizona RB: Chris Johnson hit the wall big-time in Week 12, churning out only 17 yards on 12 carries before leaving with a knee injury – quite concerning, considering he'd been limited with a knee issue in practice all week. He's headed for an MRI. Andre Ellington, too, departed Sunday's game with an injury, this one to his foot, the same issue that bothered him last year. That left some extra work for David Johnson, who ended up scoring a touchdown to go with his 29 total yards and will now have to take on a more featured role in this offense. He's probably the hottest pickup of the week.
Arizona WR: Despite facing a Niners defense that's been one of the most generous to opposing receivers this year, the Cards receiving crew didn't do much Sunday. Larry Fitzgerald stayed useful