Raheem Mostert

A breakout star for San Francisco in 2019, Mostert played only eight games in 2020 due to various lower-body injuries but nonetheless entered last season atop the depth chart for Kyle Shanahan. Unfortunately, the veteran back lasted only four snaps before suffering a knee injury that eventually required season-ending surgery. When he's healthy, Mostert is one of the fastest players in the league and is capable of turning any play into a touchdown, but his body simply might not be able to handle a large workload. That shouldn't be a problem this season, of course. After signing a one-year deal with the Dolphins this offseason, Mostert joins a backfield that includes Chase Edmonds and Myles Gaskin, both of whom handled lead roles at some point within the last couple seasons. There won't be enough snaps and touches to go around, and while Mostert is the most dangerous runner of the bunch when he's in top form, that might not be enough to guarantee regular production.

There's no debate that Mostert is one of the most dangerous open-field runners in the NFL. He scored only three touchdowns last year, but on two he recorded the two fastest top speeds on a scoring play all season, including a league-leading 23.09 mph on an 80-yard scamper in Week 2. Unfortunately, the 29-year-old sprained his MCL before halftime that week and never fully recovered, beginning a pattern the rest of the season that saw him miss a couple games, return for a couple and then suffer a new lower-body injury that sidelined him once again. Even splitting touches with Jeff Wilson late in the campaign wasn't enough to keep Mostert healthy. All told, he still averaged at least five yards per carry for the second consecutive year, and his 16-game pace would have been enough for his first 1,000-yard season, but the injuries are impossible to ignore. Plus, Wilson proved in 2020 that he's deserving of a role once he recovers from a meniscus tear, and the 49ers also signed Wayne Gallman and drafted Trey Sermon (third round) and Elijah Mitchell (sixth round). Even if he earns the lead role in Kyle Shanahan's backfield, Mostert won't necessarily handle a large workload. Whether he can be protected enough to keep him in the lineup all season remains to be seen.

The 49ers backfield had a lot of mouths to feed last year, but Mostert announced early he wasn't going to be lost in the shuffle. A 151-yard eruption in Week 2 made him a waiver-wire darling, and while he had ups and downs afterward, by season's end he had moved to the top of the depth chart in Kyle Shanahan's RB-friendly offense. Mostert found the end zone at least once in every game Weeks 12 to 17, piling up 515 scrimmage yards and eight total scores in those six games, before sending the Packers home in the NFC championship game with 220 rushing yards and four touchdowns. Not bad for a guy who was typecast as a special teams player and bounced through five organizations in his first three NFL seasons after going undrafted out of Purdue. Mostert's best asset is his electric speed in the open field - he runs a 4.34 40 - and no back in the league turned a larger percentage of his carries into gains of at least 15 yards. He even flashed a bit of power when necessary, ranking 18th among 46 qualified running backs in broken tackle rate and 23rd in average yards after contact (2.2). Mostert said he bulked up this offseason in anticipation of a larger workload this year, though Tevin Coleman and Jerick McKinnon remain on the roster, while Matt Breida was traded to Miami in April. Shanahan's long-standing preference for multi-player backfields makes a bell-cow role for Mostert unlikely, but even a modest increase in volume to 200 carries could allow for a big impact in an efficient offense.

Mostert was rewarded with a three-year contract this offseason after producing a career-high 261 rushing yards on just 34 carries (7.7 YPC) in addition to his excellent work as a gunner on special teams. The 27-year-old will find himself buried on the depth chart to start the year due to the addition of Tevin Coleman, but his roster spot should be safe on the basis of special teams work. In the unfortunate event that some combination of Coleman, Jerick McKinnon and Matt Breida go down to injury, Mostert would have upside in a larger role based on his brief breakout in 2018.

The journeyman running back worked his way onto San Francisco's 53-man roster last season, mainly contributing on special teams (just six carries in 11 games). Jerick McKinnon's season-ending knee injury does create a slight opening, but the Niners seem prepared to move forward with Alfred Morris and Matt Breida splitting work. Mostert likely will take most of his snaps on special teams.

Already a journeyman running back (five teams in two seasons), Mostert entered camp as a long shot to make the 53-man roster, but an impressive showing in the preseason allowed him to survive cutdown day. He mostly figures to contribute on special teams, though a role on offense isn't entirely out of the question.

Entering his second NFL offseason, Mostert appeared to have turned some heads during the course of Cleveland's offseason program and is reportedly firmly in the mix to compete for the Browns' No. 4 running back gig, if not contend with Glenn Winston for No. 3. Thanks to his speed, Mostert could also secure a role on special teams to boot. Ultimately, Mostert seems poised to earn a place on the Browns' regular season roster and will likely make his biggest impact returning kickoffs.

Mostert went undrafted in May. He’ll get a look during training camp, but he’ll have to leap-frog fellow running back Kenjon Barner for a shot at the 53-man roster. Even then, he’ll hardly see the field.