JACKSONVILLE, Fla. – As Keaton Mitchell finished his ninth carry of the game against the Jaguars Sunday evening, picking up the Ravens’ 19th first down, he crumpled to the ground.

His teammates gathered around him, with a few kneeling, as the trainers checked him out and helped him off. After a short stint in the injury tent, Mitchell was carted off the field. After the game, head coach John Harbaugh said the team expects Mitchell to be out for the season with a “significant” knee injury; the Ravens plan to add Melvin Gordon, who has appeared in two games this year, to the active roster to replace Mitchell.

“He’s been a playmaker for us,” running back Gus Edwards said. “He was today. He was kind of getting a rhythm going tonight. It’s real unfortunate. But no matter what it is, he’s going to be good.

“Imma just be there for him, keep checking up on him, making sure I’m in his head with positivity.”

Mitchell finished with nine carries for 73 yards and two catches for 15 yards. At the time he left, he was the leading rusher in a game the Ravens would eventually win 23-7.

On the play Mitchell was injured, his knee appeared to bend awkwardly as he landed (it was bad enough the broadcast opted not to show replays).

Mitchell, an undrafted rookie, has quickly become an essential part of the Ravens’ offense. His debut was delayed by a shoulder injury, which placed him on injured reserve but, once he was healthy, he showed impressive speed. In his third game back, the first that he was given any carries, he had a 60-yard run for a touchdown.

“Obviously, it sucks that, especially, a rookie coming in and stepping in, and playing how he was, he gave us a spark,” center Tyler Linderbaum said. “I feel for him, praying for him. And it’s gonna be a long recovery for him. But we’re gonna be by his side and helping him along the way.”

With J.K. Dobbins’ Achilles injury in the first game of the season, Mitchell’s success has been critical. Before he became a consistent contributor, the Ravens were relying on Edwards, who is known for his power, and Justice Hill, who is known for his blocking and shiftiness. Mitchell added an element of speed that was previously missing.

This season, he has had 47 carries for 396 yards in seven games. He is averaging 8.4 yards per carry, which leads the Ravens’ running backs. Sunday was his second-most productive game of the season.

Gordon, 30, is a two-time Pro Bowler. He played against the Browns and Colts this year, carrying 13 times for 53 yards while grabbing three passes for 46 yards.