Marcus Peters is a two-time Pro Bowler. (Bill Kostroun/Associated Press)

It wasn’t the greatest day for Marcus Peters. The Chiefs’ star cornerback couldn’t stop his team from getting torched by Jets wide receivers in a 38-31 loss Sunday, and in a moment of frustration late in the game, he threw a penalty flag into the stands at MetLife Stadium.

Peters was reacting to a holding penalty that had been called on a Kansas City teammate, giving New York new life near the end zone, but the wackiness didn’t stop there. While officials huddled to discuss the sequence, ultimately giving Peters an unsportsmanlike conduct penalty, he simply walked off the field altogether, apparently in the belief that he had been ejected.

A few moments later, Peters ran back onto the field, but it appeared that, in the meantime, he had taken off his socks and gloves and was in too much of a hurry to return to put them back on.

“I don’t know what was said to him or not said to him,” Chiefs Coach Andy Reid said after the game. “But he thought he was [ejected]. That’s why he came back out.”

“Probably a little frustration there,” Reid added. “I’m not saying that [the penalties] shouldn’t have been called. I’ve got to look at the tape on that. You’re down there and competing and we’ve had a few of those games where we’ve had that. It’s a bit frustrating.”

CBS announcers said during the game that they had never seen a player throw a flag into the stands. Almost as rare has been the Chiefs’ collapse, as the team started the season 5-0, including wins over the Patriots, Eagles and Chargers, but is now just 6-6 and in grave danger of missing the playoffs altogether.

Peters, 24, is in his third season in the NFL, having been a Pro Bowl selection his first two seasons and a first-team all-pro honoree in 2016. One of the NFL players who have regularly staged protests before games this season, Peters has taken to coming out of the tunnel after the national anthem is performed, after sitting on a bench during the song earlier in the season.

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