The Italian was a subdued figure on the touchline as his Chelsea side were well beaten by former manager Jose Mourinho's United team.
Chelsea failed to register a single shot on target in the 90 minutes, the first time it has happened since September 2007 when ironically United beat them 2-0 at Old Trafford.
Chelsea boss Antonio Conte wears cap and suit combo against Man United Mon, April 17, 2017
Antonio Conte baffled fans with his bizarre fashion choice on the touchline as Chelsea took on Manchester United at Old Trafford on Sunday
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Antonio Conte raised eyebrows with his fashion choices against Manchester United
Several Blues players underperformed while Thibaut Courtois and Marcos Alonso missed the match through injury and illness respectively.
Chelsea's lead over Tottenham at the top of the Premier League is now down to just four points with six games left to play.
Chelsea boss Antonio Conte looks dejected
And after the match, Conte blamed himself for the loss saying he failed to give the players enough motivation.
But when asked if he had a message for his players, Conte told NBC Sports: "There isn't a message for my players because the situation is very clear.
"If we want to write history, it is important to try to do very well, better than today."
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