Wasahington Redskins quarterback Robert Griffin III was fined $10,000 for wearing an unauthorized shirt, according to The Washington Post.

Per the report, Griffin wore unauthorized apparel before the Redskins' preseason game against the Pittsburgh Steelers. The shirt said: "Operation Patience," as a reminder he needs to remain patient as he works his way back from knee surgery.

Under NFL rules, players aren't allowed to wear unauthorized apparel on gamedays during pregame warmups.

Griffin was fined $10,000 by the NFL last season for wearing Adidas during a press conference. Griffin is an Adidas endorser.

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Aaron Wilson covers the Ravens for The Baltimore Sun.