United squad appear in high spirits after Lukaku jokes with Nemanja Matic

On the back of an impressive World Cup campaign which saw his nation reach the semi-finals, Belgium international Romelu Lukaku appears to be fitting in with his United teammates.

Lukaku, 25, uploaded a video on Instagram which showed Serbian midfielder Nemanja Matic being measured for his body fat. On the video, United's no. 9 can be heard shouting "Damn boy, zero per cent fat... zero" in the background. 

The Belgian forward also joked around in the gym with Chilean "friend" Alexis Sanchez, suggesting there is a good morale in the United camp although following a rather disappointing pre-season, which included a 4-1 defeat to rivals Liverpool.  

The 'Red Devils' begin their Premier League campaign at home to Leicester City on Friday evening.