It was a thrilling match at Stamford Bridge which United won 3-2, but will unfortunately be remembered for some dubious decisions by the referee who chose to show Fernando Torres a second yellow card for diving, reducing the Blues to nine men after Branislav Ivanovic had been sent off earlier.
Torres went down under a challenge from Jonny Evans but Clattenburg deemed it to be a dive, and brandished a yellow card.
However, Di Matteo was adamant there was contact between Torres and Evans and believes the Manchester United defender should have been sent off as he denied the Spaniard a goalscoring opportunity.
"The key decisions from the referee today [Sunday] probably influenced the result," said Di Matteo.
"He sent off Fernando Torres and the third goal is offside and it clearly has decided the game.
"He's (Torres) put the ball between his legs and is through and gets a kick on his shin and he goes down.
"It's a free-kick for us and I think it should have been a sending off for Evans because he's through to the goal.
"Everything went for United and that really makes us unhappy."