Robert Griffin III has insisted that he has "no time to feel proud" of his recovery from knee surgery.
The Washington Redskins quarterback was believed to be a doubt for the start of the 2013 NFL season after tearing two knee ligaments in January, but was cleared by doctors to return to practice earlier this week.
In a text to USA Today, the offensive rookie of the year wrote: "No time to feel proud. Just more work and winning to do.
"People want you to only think of yourself and your career when you are a team player, and when you are selfish, then they want you to only think of the team."
Griffin completed 3,200 passing yards and 815 rushing yards during his first season in the league, helping the Redskins reach the playoffs.
