The San Francisco 49ers were left counting the cost of a 31-13 victory over the New York Jets on Sunday as five key players suffered injuries including star defensive end Nick Bosa.
Bosa, a talismanic presence in the 49ers defense, was carted off in the first half with what head coach Kyle Shanahan later said was suspected to be a season-ending cruciate ligament injury to his right knee.
He was joined on the 49ers' injured list by defensive tackle Solomon Thomas, who was also feared to have suffered a serious knee injury just three plays after Bosa left the game.
"Solomon is in the same boat as Bosa," Shanahan said afterwards.
"He has a better chance of not being that from what I'm told. But we'll have to wait and see."
Quarterback Jimmy Garoppolo (ankle sprain) and running backs Raheem Mostert and Tevin Coleman (knees) were also injured.
San Francisco coach Shanahan said later players had complained about the "sticky" playing surface at the Jets' MetLife Stadium in East Rutherford, New Jersey.
"As far as the feeling that was on the sidelines, that's as many knee injuries and ankle stuff and people getting caught on the turf as I've ever been a part of," Shanahan said.
"I know our players talked about it the entire game, just how sticky the turf was, and I think that was the first time people played on it. It was something our players were concerned about right away."
The 49ers, beaten in last season's Super Bowl by the Kansas City Chiefs, face another trip to MetLife Stadium next weekend when they take on the New York Giants in the second game of their road trip.