It all started so well for Romelu Lukaku at Old Trafford.
When the big Belgian moved from Everton for £75 million in the summer, it was speculated that he wasn't Mourinho's first choice.
After moves for Antoine Griezmann and Alvaro Morata failed to materialise, United stumped up the cash for Lukaku and allowed all-time record scorer Wayne Rooney to depart on a free the other way.
However, the 24-year-old made a blistering start to his career as a Red Devil by netting 11 times in his first 10 games.
His goals have helped make United a legitimate title contender for the first time since Sir Alex Ferguson retired, but after failing to score in his last seven games for United, his critics have begun to pipe up.
Lukaku did manage to score a brace for Belgium in their 3-3 draw with Mexico earlier this week to become Belgium's joint all-time record goalscorer - at 24 remember - but can he take his form back to United?
After netting the confidence boosting goals, Lukaku sent out a tweet thanking his 'real fans', seemingly a shot at the United fans that has criticised his recent form.
'Real fans' huh? It's never a good idea to hit back at the fans, but maybe he's just following his manager's lead after Mourinho's recent not-so-subtle comments in the United programme notes.
As you can see from the tweets below, while most fans continue to back him, plenty United fans weren't overly happy.
Speaking after Lukaku's goalless display against Spurs at the end of October, Mourinho publicly backed his forward.
“The fans are the fans and I also told [on Saturday] that the fans pay for their tickets and are free to express themselves the way they want to express,” Mourinho said. “But my job, when I feel they deserve it, is to protect my players.
"Romelu is one of the players that should be untouchable in terms of the respect of everyone. It’s not one goal or the ball goes against the post or a save by the opposition keeper that can make Romelu’s contribution below the top level.
“He is playing extremely well for us and yes I have to protect my players when I feel they deserve it. And Romelu always deserves it because what he does for the team is fantastic. Playing football for a striker isn’t just about scoring goals.
"So for me [he is] untouchable in my team and I think he should be untouchable in support from the fans. But fans are fans, they pay the ticket and do what they want. As a manager I feel duty to protect my players when I feel they deserve it."
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