AFL: Assumption Fail legality - A discrimination danger for employers

It has recently been reported that a Victoria-based AFL player, whose professional netballer wife will be playing for a Queensland club in 2021 (and relocating to that state with the couple's very young child to do so), has been told by the AFL club for which he plays that he should leave and join another club. The alleged reason? Officials and some fellow players at his current Victorian club believe he will be too distracted to properly concentrate on football next year, with his wife and child interstate.

As is the case with many sports stories, there have been a series of claims, denials and counterclaims. As such, the veracity of the story remains uncertain. Setting that aside, and treating this as a hypothetical scenario for the purpose of the brief discussion in this article, could an employer legally do this to an employee?