Antonio Brown missed the last game of Pittsburgh’s season not because of a knee injury but because he sat out practice last week after getting into a dispute with a teammate.

According to the Pittsburgh Post-Gazette, a heated argument between Brown and an unspecified teammate happened Wednesday morning during a walk-through. The disagreement ended in Brown throwing a football at one of his teammates. Brown sat out the rest of the week, which was reportedly his decision.

Brown, who leads the league in receiving touchdowns, still expected to play on Sunday, per the Post-Gazette, even after missing both a walk-through and a meeting on Saturday. Ultimately, after not getting on the field in the first half, Brown reportedly left Heinz Field.

One teammate reportedly called Brown ahead of the game, but he did not pick up. An unnamed player told the Post-Gazette that the situation was “the worst I’ve ever seen” and its handling affected his desire to play.

The Steelers pulled out a 16-13 win over the Bengals but will miss the playoffs after going 9-6-1. More important, though, is what happens next with Brown — their best offensive player and a face of the franchise — is now unclear.