Lukaku is personally in a rich vein of form, having made an immediate impact at the start of his United career, with six goals in as many games for the Reds, as well as four in two matches for Belgium to help them qualify for next summer's World Cup finals during the recent global break.
The Portuguese, though, did play down his record in his second seasons at clubs. You have better conditions to work and get those results.
The Reds once again showed that goals can be spread around the team this season as Lukaku's fellow countryman Marouane Fellaini and Marcus Rashford also netted against the Swiss champions at the Theatre of Dreams.
United are one of the favourites to be Premier League champions come May, but Mourinho has consistently refuted that the Reds are the favourites.
"So it's really complicated for me to answer this but what I know is that they're two managers that are obsessed with improving their players, their team and their club".
Mourinho may be talking about players like Danny Welbeck and Javier Hernandez, who he claimed he wouldn't have sold had he been in Louis van Gaal's position. As the Merseyside club prepare to visit Old Trafford for game week 5, the occasion promises to be much more than just another game of football.
Lukaku's Old Trafford career has begun in superb style, with six goals in six games, while another striker who had been on the United radar, Alvaro Morata, has scored three times in four Premier League games for Chelsea.
The Belgium worldwide has made a brilliant start to his Old Trafford career following a £75m switch to Manchester United form Premier League rivals Everton. We paid what Everton asked for.