A marketing tie-up between General Motors Co.'s Chevrolet brand and the Manchester United soccer club led to the ouster of Joel Ewanick, GM's global marketing chief, Doron Levin reports on Fortune.com.

A source who declined to be named, citing the legalities of Ewanick's abrupt departure, said GM  senior management had identified "improprieties" in connection with the Manchester United deal announced in late May. The source declined to discuss nature of the impropriety. 

A GM spokesman, Greg Martin, said Ewanick's job performance hadn't met the company's expectations. Ewanick resigned on Sunday. He declined to comment.

Read more: Fortune.com