DK Metcalf punches fan: Steelers WR gets into physical altercation with spectator during Lions game

Every game matters greatly for the Pittsburgh Steelers at this point in the season, but the focus coming out of Sunday's game against the Detroit Lions might not be solely on football.

Steelers wide receiver DK Metcalf was seen punching a Lions fan from the sideline during the first half on Sunday, sending a closed fist in the direction of a fan in the crowd while Pittsburgh's offense was off the field.

Metcalf wasn't punished for the punch in the moment, but discipline could be on the way once the NFL reviews the incident.

Here's a look at the moment Metcalf punched a Lions fan on Sunday.

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DK Metcalf punches Lions fan

CBS cameras captured the final moments of a tense interaction between Metcalf and a Lions fan wearing a blue wig in the first half on Sunday, with Metcalf throwing a punch in the fan's direction.

It wasn't clear from the replay whether Metcalf connected with the fan's face or shoulder, but he walked away after throwing the punch. 

DK Metcalf appears to have an altercation with a Detroit fan pic.twitter.com/a478Zjg3tR

It's impossible to know what the fan might have said to Metcalf, but that likely won't matter very much to the NFL as it reviews the incident. Metcalf was not disciplined in-game for the punch, but his status for the Steelers' Week 17 game against the Cleveland Browns is likely to be a major storyline coming out of Sunday.

Metcalf struggled in the first half against the Lions, hauling in only one of six targets from Aaron Rodgers.