Major League Soccer has terminated the contract of Montreal midfielder Matko Miljevic following claims he played for an amateur team under a fake name.
Widespread reports in Canada also alleged the player was banned indefinitely for punching an opponent while turning out for the local side.
He was "engaging in conduct detrimental to the league and violating his standard player agreement", MLS said.
Montreal confirmed the 22-year-old American was no longer with the club.
Montreal head coach Hernan Losada last week confirmed an investigation was under way following the reports.
It was claimed Miljevic had played three games for a friend's team in a Quebec amateur league - scoring six goals - after becoming frustrated with a lack of playing time at Montreal.
Miljevic made eight substitute appearances for Montreal this season.
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