49ers running back Raheem Mostert announced on Twitter Tuesday that he is set to undergo season-ending surgery to repair his knee.

The 49ers' running back room will be without a key piece for the foreseeable future. Raheem Mostert is headed to injured reserve after chipping cartilage in his knee during Sunday's win against the Lions.

49ers running back Raheem Mostert was ruled out against Detroit with a knee injury. Keep track of every injury from every Week 1 game.

You have lineup questions. We have answers. At least we hope. Start 'Em, Sit 'Em is back for the 2021 NFL season.

Which veteran starters could find themselves in backup duty by the end of the month? Gregg Rosenthal identifies 14 players skating on thin ice in training camp.

Will Matthew Stafford deliver for the Rams? Can a healthy Nick Bosa get the 49ers back on track? Adam Maya provides a training camp preview for the NFC West, with position battles and key players to watch across all four rosters.

Maurice Jones-Drew ranks all 32 RB1s heading into the 2021 NFL season. Ezekiel Elliott lands just outside of the top five while a few second-year backs are knocking on the door of the top 10. Check out MJD's full pecking order.

After an injury-riddled 2020 season, the San Francisco 49ers are back with a roster that appears loaded on paper. Can Kyle Shanahan get them back to the Super Bowl? Adam Rank examines the state of the franchise ahead of the 2021 campaign.

Which roster looks best in the NFL's toughest division? Is the Rams' top-heavy blueprint built for success? Can the 49ers return to the Super Bowl with a rookie at quarterback? Gregg Rosenthal projects the starters for every team in the NFC West.

Washington and Cleveland just turned putrid seasons from 2019 into playoff journeys in 2020. Which NFL teams could follow suit in the 2021 campaign? Marc Sessler spotlights four particular franchises.

Steelers coach Mike Tomlin said Tuesday that they hope to see running back James Conner (quad), linebacker Vince Williams (COVID-19 list) and offensive lineman Kevin Dotson return Sunday.

Adam Rank breaks down which running backs you should start and which ones you should sit for Week 15 of the 2020 NFL fantasy football season.

Can Philip Rivers' Colts push their way into the playoffs? Will Kyler Murray's Cardinals stop their skid? Gil Brandt eyes fringe teams he's not counting out.

Kyle Shanahan's 49ers are in the midst of a season in which they're encountering incredibly unfortunate amounts of injuries, but he's not pointing to the two reserve lists -- injured and COVID-19 -- with fingers of blame.

Bobby Turner has played an instrumental role in some of the most impressive rushing performances of the last 25 NFL seasons. Former personnel executive Scott Pioli draws from his experience as a colleague of Turner's to provide insight on why the 49ers' RBs coach has had so much success developing unheralded players into some of the biggest NFL stars, including Hall of Famer Terrell Davis.

49ers coach Kyle Shanahan announced Monday that running back Raheem Mostert sustained a high ankle sprain in the team's Week 6 win 24-16 win over the Rams and is "most likely" headed to injured reserve.

Gregg Rosenthal spies teams that faced a Week 6 fork in the road. Did D'Andre Swift's Lions turn toward the light? Are Kirk Cousins' Vikings bound for darkness?

Week 4's in the books. So ... what's hot and what's not? Marc Sessler has his finger on the NFL pulse, and this dispatch opens with a magical moment for one long-suffering fan base.

Is there any rushing duo better than the Browns' Nick Chubb and Kareem Hunt? Nick Shook lists the NFL's top 10 backfields.

Dual-threat quarterbacks are off to a hot start in 2020. Maurice Jones-Drew divides these multi-talented QBs into five tiers. Plus, there's a new No. 1 in his top-15 running back rankings.

Niners running back Tevin Coleman's knee injury is expected to have him sidelined for about four weeks, coach Kyle Shanahan said. Tight end George Kittle returned to practice.

The 49ers might have finally gotten some good news involving its MRI machine. Raheem Mostert's latest tests revealed an MCL sprain, leaving the team optimistic its lead back won't be out for an extended period, Tom Pelissero reports.

Fresh off the second Sunday of the NFL's 2020 season, Adam Schein spotlights developments he loved (SEE: Josh Allen silencing critics), liked (Arizona hitting 2-0) and loathed (another Falcons face-plant).

San Francisco defensive end Nick Bosa was carted off Sunday with what is likely a torn ACL. He wasn't the only 49ers player to be knocked out.

Maurice Jones-Drew makes a plea to NFL offensive coordinators to utilize running backs in the passing game more often. Plus, there's a new player in his ranking of the top 15 RBs.

NFL Network Insider Ian Rapoport explains why San Franciso 49ers running back Raheem Mostert opted for season-ending knee surgery.

NFL analyst Brian Baldinger breaks down what got him excited about the San Francisco 49ers rookies and offensive line during their win over the Detroit Lions in Week 1.

San Francisco 49ers running back Raheem Mostert announced that he will undergo season-ending knee surgery.

NFL Network Insider Ian Rapoport reports San Francisco 49ers place running back Raheem Mostert on IR, expected to miss 8 weeks.

NFL Network's Adam Rank shares his running back starts and sits in fantasy football for Week 1 of the 2021 season.

NFL Network's Patrick Claybon, Cynthia Frelund, Adam Rank and Michael F. Florio share their top flex players to start in fantasy football in Week 1.

NFL Network's Patrick Claybon, Marcas Grant, Michael F. Florio and Adam Rank examine crowded running back rooms in fantasy football for 2021.

NFL Network's Patrick Claybon, Marcas Grant, Kimmi Chex and Michael F. Florio spotlight four players who deserve more love in fantasy drafts entering 2021.

NFL Network's Mike Rob's shares his top 5 RBs for Week 1 of 2021.

Watch highlights from the Preseason Week 3 matchup between the Las Vegas Raiders and the San Francisco 49ers.

Watch the San Francisco 49ers' top plays vs. Las Vegas Raiders during Preseason Week 3.

San Francisco 49ers running back Raheem Mostert stiff-arms Las Vegas Raiders defender to the ground along the sideline.

San Francisco 49ers running back Raheem Mostert squeezes through hole for 26-yard sprint.

Relive the top moments from every team's top running back play from the 2020 NFL season.

San Francisco 49ers RB Raheem Mostert dazzled in the 2019 NFC Championship game with 220 rushing yards and 4 TDs vs. the Green Bay Packers becoming the first player in NFL history with over 200 yards and 4 touchdowns in a playoff game.

Watch the best plays by the San Francisco 49ers from the 2020 NFL season.

Next Gen Stats ranks the top 10 runs of the 2020 NFL season by rushing yards over expected.

Next Gen Stats ranks the fastest 10 ball carriers of the 2020 NFL season.

Watch highlights of the plays that featured the most yards after the catch in the 2020 NFL regular season.

Watch the game highlights of the Week 14 matchup between the Washington Football Team and the San Francisco 49ers.

NFL Media's Michael F. Florio shares the best and worst fantasy matchups in Week 14.

Watch the Buffalo Bills vs. San Francisco 49ers highlights from Week 13 of the 2020 season.

NFL Network's LaDainian Tomlinson and Terrell Davis reveal their Top 3 running backs for Week 13.

Five awesome things from the San Francisco 49ers' Week 12 win over the Los Angeles Rams.

San Francisco 49ers RB Raheem Mostert emotional after win over Rams in Week 12.