A long and aggravating night for the Detroit Lions at Arrowhead Stadium ended when Brian Branch threw a punch at Kansas City Chiefs wide receiver JuJu Smith-Schuster, sparking a brief brawl between players from both sides.

It was about the most fight the Lions displayed all evening.

The Chiefs dominated on both sides of the ball, bouncing back from a sloppy performance in Jacksonville and refusing to drop two games under .500. Kansas City’s defense stifled Detroit’s usually explosive offense, holding it to barely half its scoring average, while their own attack marched up and down the field en route to a 30-17 win on Sunday night.

Then came the fireworks.

As red explosions filled the sky to celebrate Kansas City’s victory, Patrick Mahomes reached out to high-five Branch near midfield. The Lions safety ignored him, prompting Smith-Schuster to step in and exchange words with Branch.

Branch responded by throwing a right-hand punch that dropped Smith-Schuster to the turf.

The veteran receiver quickly jumped up and charged at Branch, who was playing through an ankle injury that sidelined him during practice all week. Chiefs running back Isiah Pacheco tried to separate them, but Branch managed to rip off Smith-Schuster’s helmet as players from both teams stormed into the scuffle.

Eventually, coaches and teammates pulled everyone apart, and the players finally headed to the locker rooms. Branch could now be facing a fine or even a suspension for his outburst.

The defeat ended Detroit’s four-game win streak and ruined their chance at a rare back-to-back victory at Arrowhead. The Lions surrendered 355 total yards, forced just one punt, and couldn’t make key stops late in the fourth quarter to give their offense another shot.

Jared Goff threw for 203 yards and two touchdowns to Jameson Williams and Sam LaPorta, while Amon-Ra St. Brown was limited to 45 yards receiving. Jahmyr Gibbs totaled 65 yards on 17 carries, with 32 of those coming on the opening drive when Detroit looked ready to score.

David Montgomery took a direct snap near the goal line and tossed to Goff, who motioned out, caught the ball, and powered into the end zone. But after the play, officials conferred and ruled Goff hadn’t been set — despite no flag being thrown — nullifying the touchdown for illegal motion.

A delay-of-game followed, forcing Detroit to kick a field goal for a 3-0 advantage.

It set the tone for a frustrating evening for head coach Dan Campbell and his team.