McDonald suffered a broken leg Sept. 26 against San Francisco, an injury that landed him on the injured reserve/designated to return list and kept him out for the following eight weeks.
To the surprise of many, McDonald returned Nov. 24 against Chicago and jumped right back into the starting lineup. Although he posted six tackles, he was clearly rusty and had his share of missed tackles and blown coverages.
Playing the Niners in the rematch last week, McDonald moved around better and had five tackles with a pass breakup. The numbers weren't much different but the performance was clearly better.
"Much better this week than he was last week," coach Jeff Fisher said. "Last week was his first one back with the injury. At times he had difficulty decelerating last week. This week he was a completely different player. I think a lot had to do with the surface and then an extra week of healing and practice, but he played pretty well."
Even McDonald was quick to acknowledge that his speedy recovery and return to the field left him struggling to catch up. After playing against the Bears, the Rams limited McDonald's work in practice last week in an effort to keep soreness from setting in.
"I hadn't played in eight weeks," McDonald said. "So it was just giving me some time early in the week to recoup but other than that I'm fine. I haven't played in a while but nobody cares about that once you're on the field. I've got to go out there and play and I felt like today for the most part I did what I needed to do."
As a rookie starter, McDonald's development over the season's final four weeks is quite important to the future of the defense. The Rams clearly view him as a key cog to the defense moving forward and believe he has long-term potential to hold down the spot for years to come.
The time McDonald lost to injury set back his development, though by most accounts he's a quick learner ahead of his time in terms of the mental aspects of the game.
But McDonald plays safety, a position that has long been a problem spot for the Rams and one where they've rarely had two solid starters working in tandem. McDonald could be one but it seems likely the Rams will need to address finding a running mate for him this offseason.
At 6-foot-2, 219 pounds, McDonald represents an obvious solution as an in-the-box safety, playing the more physical, run stopping role. That doesn't mean he can't be used in coverage -- his pass breakup against the Niners was the other play he made against tight end Vernon Davis -- just that the Rams could improve the secondary by adding more of a ball hawk next to him.
Of course, McDonald taking advantage of the final four games to shorten his learning curve would be helpful not only for him but for anyone who lines up next to him in 2014.
"I think he'll finish up strong," Fisher said. "There were a couple plays [Sunday] that you say, 'Wow, that's why we drafted him.' First run game, I think, of the third quarter, we had both T.J. and Alec [Ogletree] show up at the same time on the back for a 3-yard loss. It's pretty impressive to watch their speed and their physical approach."