Tempers flared early in Detroit ahead of an NFC North matchup with an unusual dispute.

Green Bay Packers head coach Matt LaFleur and a Detroit Lions fan were separated on the field before Thursday night’s clash.

The ruckus appeared to occur right before the national anthem when Lions fans were on the field holding the flag for the game.

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Apparently, though, a fan in a Brian Branch jersey took it a bit too far, to the point LaFleur told him to "shut the f--- up."

Several Packers players and referees intervened before the fan walked away, excited about what had just happened.

Fans holding the flag took their phones out to record the argument. 

And it wasn’t an ideal start for the Packers once the game actually started. 

A defensive penalty on a third and goal gave the Lions a fresh set of downs, and David Montgomery ran in for a score on the game’s first drive. After Detroit made it 10-0, the Packers cut into the lead with a Josh Jacobs touchdown in the second quarter.

The Lions took a 17-7 lead into the locker room, but the Packers scored touchdowns on back-to-back drives and benefited from a costly Jared Goff interception to lead 21-17.

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The Lions and Packers have combined to go 20-4 this season and are first and third in the division, respectively. Detroit is looking to set a franchise record with its 11th straight victory.

Both teams earned home victories on Thanksgiving.

The Lions defeated the Packers last month, 24-14, at Lambeau Field.

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