Jadeveon Clowney has admitted that he is not back to full strength following sports hernia surgery earlier this year.
The Houston Texans outside linebacker, who was the number one pick in this year's Draft, had the operation after minicamp, and has been limited at the start of the team's training camp this week.
The 21-year-old told reporters: "I don't know the percentage but I know I ain't 100%."
The Texans face the Arizona Cardinals in their opening pre-season game on August 9.