Baltimore Ravens quarterback Lamar Jackson exited and did not return to Sunday's 10-9 win against the Denver Broncos due to a knee injury, the team announced.
After the game, Ravens head coach John Harbaugh said Jackson's injury is not season-ending.
"We'll get more tests tomorrow," Harbaugh said. "If it's going to be a number, it will be days or weeks."
Jackson suffered the injury taking a sack from Jonathon Cooper on the last play of the first quarter.
The 25-year-old was initially labelled as questionable to return before being ruled out entirely.
Baltimore's season fell apart last year when Jackson went down with an ankle injury in December. He hasn't missed a game this season for Baltimore, which is tied with the Cincinnati Bengals atop the AFC North at 7-4.
-With files from the Associated Press
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