SPARTANBURG, S.C. (AP) Carolina Panthers defensive tackle Vernon Butler sprained his left knee during the preseason game against the Houston Texans.
The team announced the injury on Friday.
Butler, the team's first-round draft pick in 2016, went down in the first quarter of Carolina's 27-17 preseason win over the Texans on Wednesday night. He hobbled off the field, went to the locker room and didn't return to the game.
It's unclear how much playing time Butler will miss while rehabbing from the injury. Butler's rookie season with the Panthers was slowed by a high ankle sprain.
The Panthers open the regular season Sept. 10 against the San Francisco 49ers.
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