Manchester United forward Cristiano Ronaldo left Old Trafford before full-time in Wednesday's Premier League win over Tottenham.
It is understood Ronaldo briefly went into the dressing room before leaving the stadium.
Manager Erik ten Hag said after the game that he would "deal with" the issue on Thursday.
"I have seen him, but I haven't spoken with him," said Ten Hag.
United had made only three of their five permitted substitutions when Ronaldo got off the bench, shortly after Ten Hag brought on Christian Eriksen and Anthony Elanga.
Ten Hag said after that game that he had "no problem" with Ronaldo's reaction but the player must convince him "he has to stay on".