Washington Redskins quarterback Robert Griffin III was fined $10,000 by the NFL for wearing unauthorized apparel before Monday night's preseason game against the Pittsburgh Steelers, a league confirmed Thursday.

The second-year quarterback wore a T-shirt with the words "Operation Patience" on it while warming up before the game. Griffin did not play in the game as he continues to work his way back from a surgically repaired right knee.

Robert Griffin III's pregame apparel Monday night proved costly, as he was fined $10,000 by the NFL. AP Photo/David Drapkin

Griffin dressed in full uniform during the game, but the NFL requires players to follow their uniform rules before the game, too.

The NFL fined Griffin $10,000 for wearing adidas clothing at a postgame news conference last season. The league has a deal with Nike.

Griffin inched forward a little more in his rehab Wednesday by working against the starting defense for the first time in a full practice since last season. Griffin took 49 snaps against the scout team defense last week.

"I'm getting the team reps, and that's what I wanted, and that's what the team needed me to be out there doing," said Griffin, who has yet to play in the preseason and remains a question mark for the team's regular-season opener. "I feel good. I am confident Coach (Mike Shanahan) easing me in has helped, and giving me the extra reps has helped now. My eyes are set on Philly."

Griffin said Dr. James Andrews told him Monday after Andrews examined him before the Redskins played Pittsburgh that his leg looked strong and his movement was good. Andrews' message: Stay the course.

Information from The Associated Press was used in this report.