SPARTANBURG, S.C. (AP) Injuries have become the main focus of the Miami Dolphins and Carolina Panthers on the first day of their joint practices, not fights that have headlined recent joint workouts between teams.

Panthers receiver Kelvin Benjamin was carted off the field with a sprained left knee and will have an MRI Wednesday to determine the full extent of the injury. Coach Ron Rivera said the team is hopeful Benjamin didn't tear any ligaments.

The news isn't as positive for Dolphins safety Louis Delmas.

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A person familiar with the situation told The Associated Press on Wednesday that for the second time in less than 10 months Delmas has torn the ACL in his right knee. The person spoke on condition of anonymity because the team has not publicly announced the extent of the injury.

Delmas first tore his ACL last December against Baltimore.

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AP Sports Writer Steven Wine in Miami, Florida contributed to this report.

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