Mourinho has fallen out with several United players during his time at Old Trafford, including Paul Pogba, Alexis Sanchez and Eric Bailly.
The United manager has also publicly criticised his players with Luke Shaw and Anthony Martial both coming under fire in the last 12 months.
But Lukaku believes his United teammates should just deal with it.
Asked what Mourinhos relationship is like with other United players, Lukaku told Bleacher Report: I think he has a good relationship with the players.
I dont really pay attention to what his relationship is with the other players, to be honest.
I dont think its something that should affect me.
If he [Mourinho] has an argument with somebody I mean, deal with it, man.
Youre a grown-ass man, deal with it.
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