Vikings running back Christian Darrisaw, one of the best blindside blockers in the NFL, will require season-ending knee surgery.

Darrisaw was hit from behind by a Rams defender tackling running back Aaron Jones just before halftime of the Vikings’ 30-20 loss on Thursday night. He fell to the grass holding his left knee. Teammates circled around him, fearing the worst. Those fears became reality on Friday when tests confirmed Darrisaw’s season is over after seven games. He suffered damage to his ACL and MCL, Vikings coach Kevin O’Connell said in a video news conference Friday.

“It obviously hurts,” right tackle Brian O’Neill said after the game at SoFi Stadium. “Anytime you lose one of the best players at his position in the NFL, for any period of time, even just half, it’s going to be felt. We’ll have to lift him. He knows he will get a lot of support here. He knows he will be a very good player here for a long time. I’m just thinking about him and praying for him now.”

The Vikings offense will have to find a path forward without a franchise cornerstone. Darrisaw was rewarded with a four-year, $76 million contract in July as the front office prioritized extensions with him following receiver Justin Jefferson’s mega-contract in June.

David Quessenberry, a 34-year-old journeyman who initially signed before last season, replaced Darrisaw for the remainder of the game and is expected to start for him on Nov. 3 against the Colts.

Regarding the play, Darrisaw was injured, O’Connell explained his decision to call a run instead of a pass with 35 seconds before halftime from the Vikings’ 3-yard line. They had three timeouts available.

“Sean (McVay) still had that one timeout left,” O’Connell said. “We ended up in that situation. They had (six defensive backs) on the field, so (I) thought maybe we could score a point… and then maybe take a timeout, reset and try to get some chunks. We have a kicker who can hit him from far away.”