and their tilt at an unprecedented five trophies in one season.
Derby manager Nigel Clough backed United's bid to conquer all after suffering a 4-1 FA Cup defeat on Sunday but Inter later showed their own relentless power as they beat city rivals AC Milan 2-1.
Afterwards, striker Zlatan Ibrahimovic said: 'If we play like this we will beat United.'
The performance bore all the hallmarks of Mourinho's Chelsea
, a muscular resilient outfit, high on confidence and self-belief.
Threat to United: Mourinho
Sir Alex Ferguson, who has only beaten Mourinho once in a dozen attempts, will see next Tuesday's Champions League clash as his biggest challenge of the season.
United are in command at the top of the Barclays Premier League, in the last eight of the FA Cup and the Carling Cup final, with the Club World Cup already in the bag.
Ferguson will warn his European champions how threats can emerge from the most unlikely places — Mourinho's Porto knocked United out of the Champions League on their way to winning the trophy in 2004 — and if any team look capable of halting United's bid for history it is Inter, nine points clear in Serie A chasing a fourth straight title.
They have lost only twice in the league in Mourinho's first Italian campaign but the former Chelsea and Porto boss was hired to win Inter's first European Cup since 1965 and he has already made two personal checks on United, who visit the San Siro for the first leg of their last-16 clash.
Ibrahimovic said: 'He has changed our mentality a little bit. We were good when he came but he's teaching us something new. We have become stronger and better and are hungry for the big games.'
Ibrahimovic, a player with a reputation for his difficult attitude, is thriving in the embrace of Mourinho, who used his old ploy of calling him the best player in the world. A little ego massage often worked to good effect with his favourites at Stamford Bridge.
But the true test of Mourinho's man-management skills comes in the shape of Adriano, the wayward Brazilian who rarely fails to disappoint in terms of focus and dedication.
Even Mourinho joked that a miracle might be the only answer when he sent him home to recuperate before Christmas.
Man-management skills: Adriano scored the opener in the Milan derby
Adriano was then banned for three games for throwing a punch at Sampdoria defender Daniele Gastaldello but there were signs of progress as he scored theopener in the Milan derby, albeit off his arm, and dedicated it to Mourinho's son, Jose Jnr. 'I want to thank the coach for putting his faith in me,' said Adriano.
'I think I did well. I'm improving bit by bit.'
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