Ryan Tannehill sustained a non-contact knee injury at Miami Dolphins training camp Thursday.

The injury is to the quarterback’s left knee, a source told Armando Salguero of the Miami Herald.

Tannehill was observed going down after scrambling during team drills. He was on the ground, surrounded by teammates, for around 15 seconds before walking off gingerly but with no pronounced limp.

The Dolphins had no immediate update for Tannehill’s status, but sources told ESPN’s Adam Schefter the team is “concerned” by the injury, while Salguero adds, citing a source, the team is fearing the worst, though that same source said Miami is still hopeful.

Tannehill suffered a season-ending left knee injury in December, spraining his MCL and ACL.

He’s been wearing a brace during camp, though he said his knee is no longer an issue.

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