Granted, he won't be doing it alone, but the "Mike" linebacker will be expected to hold things down in the middle of the field now that Fletcher is gone.
He will likely have Keenan Robinson starting next to him, but the fourth-round pick in 2012 has done little to warrant much confidence from the team, leaving Riley with much of the offseason attention.
He certainly has talent, but can he help bandage the loss of one of the best linebackers to play the game?
Riley has only been in the league for four years, but has shown much progression and development over the past two seasons—he's totaled 244 combined tackles and 6.5 sacks in that span.
Let's also not forget that he's produced those numbers while maintaining a prominent and effective role on special teams.
Riley is just 26 years old, hasn't missed a game since his rookie season and has a boatload of potential. He's been an impactful player thus far, but given the rate at which he's progressing, it looks like he could become a serious difference-maker before long.
Riley does have his faults and will definitely have to continue improving in order to more fully fill the void left by Fletcher.
He struggles in pass defense, but isn't a big liability in coverage. Riley performs well against the run and plays pretty well in zone coverage—much better than when he plays in man coverage.
He does struggle as a pass-rusher, but that's largely because his size (6'0", 238 lbs) prevents him from shedding most blockers. It's clear that he's not the ideal replacement for Fletcher, but Riley is the best option the Redskins have.
The shoes Riley is faced with filling are definitely massive, but there is a good chance he will perform well.
He now has a much better supporting cast around him, and you can expect him to take another positive step forward—especially considering how he's progressed in recent years.
Riley is just coming off of his rookie deal and has had a promising first chapter in his NFL career, which surely gives the team confidence as it hands him the reins to the defense.
The soon-to-be fifth-year pro is coming along rather nicely as a starter, and while he may not be quite at Fletcher's caliber, he's still pretty good.
Though it certainly won't be the same as when No. 59 was around, Riley should do just fine.