Pittsburgh Steelers wide receiver DK Metcalf was involved in a sideline altercation with a spectator during the team's 29-24 victory over the Detroit Lions at Ford Field.
Broadcast replays from the second quarter showed Metcalf walking toward a fan who was leaning over the front railing of the stands. The images appear to show Metcalf reach for the spectator's blue wig and then swing with his right hand.
During the live coverage, CBS sideline reporter Tracy Wolfson said: "He went over and the fan said something to him," and added, "Obviously, Metcalf did not like what he said, and you saw the swipe there. No Steelers came over to him and mentioned anything."
The spectator involved was identified as Ryan Kennedy. He told the Detroit Free Press: "I called him that, and then he grabbed me and ripped my shirt."
Kennedy described his reaction after the incident: "I'm a little shocked. Everyone's talking to me. I'm a little rattled, but I just want the Lions to win, baby."
Game officials did not witness the exchange on the field, so Metcalf remained in the contest and completed the game. He finished with four catches for 42 yards as the Steelers secured their third straight victory.
The NFL is reviewing the incident and could still impose discipline.
Steelers head coach Mike Tomlin commented on the situation, saying: "I heard about it, but I hadn't seen it and I hadn't had an opportunity to talk to DK."