PHILADELPHIA (CBS) — Philadelphia Eagles running back Kenneth Gainwell went viral for the wrong reasons on Sunday against the Washington Commanders.

A person messaged Gainwell on Instagram with an expletive following the play and for him to “hold on to the football.” Gainwell then replied to the person during halftime while the team was in the locker room.

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“Lil boy don’t text me,” Gainwell wrote back on Instagram.

Eagles head coach Nick Sirianni addressed the exchange during a press conference Monday and said Gainwell “knows he made a mistake.”

“This is part of these guys’ lives, is some of that stuff. He’s sitting at the locker. Should he respond to somebody that’s DM’ing him? No, he shouldn’t respond to that guy or that girl at all,” Sirianni said. “And so, yes of course we talked to him about that, to be locked in and focused and not worried about outside noise. He knows he made a mistake responding back to that person, who I’m assuming is an Eagles fan and then took a snapshot and posted it.”

Gainwell, who was selected in the fifth round of the 2021 NFL draft out of Memphis University, has been Philadelphia’s second string tailback this season behind Philly native D’Andre Swift.

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Gainwell has 153 rushing yards and one touchdown through seven games.

The Eagles ended up coming back to beat the Commanders, 38-31, and Gainwell finished with -4 rushing yards and five catches for 30 yards.

Despite Gainwell’s mistake Sunday, Sirianni said he still has confidence in him.