The Blues suffered their first European defeat of the season at Shakhtar Donetsk on Tuesday after falling behind to Alex Teixeira’s goal within three minutes in Ukraine.
And the Italian admits it is crucial his side start Sunday’s clash well as they look to extend their four-point lead over Sir Alex Ferguson’s men.
“When you concede an early goal it’s always a bad start to a game,” he said. “Starting the game well is very important – and both halves, not just the first half. [It’s also important] to be disciplined with the organisation and not losing that even if you do concede an early goal.”
Di Matteo admits the spirit in the Chelsea camp took a knock as a result of their midweek disappointment but the Blues boss is certain his side are well-placed to bounce back with a positive result against the Red Devils.
“We always pay attention to the players’ behaviour and the mood in the camp,” he said.
“Certainly after a defeat it’s not the best within our dressing room but we have a great game coming up on Sunday and we can show everybody that we’re a strong team.
“We are still in good shape and this group of players always responds to a bad result.”
A victory for Chelsea would open up a seven-point gap between the Blues and United but Di Matteo still feels it is too soon for the game to have a significant impact on the title race.
“It’s still a little bit early in the season for a game like this to be decisive,” he said.
“They’re a great rival of ours; we’re playing at home so we want to try and keep our home record intact and keep the distance from them.”
Di Matteo also confirmed that midfielder Frank Lampard will be out of action for a “couple of weeks” with the calf injury that forced him off in the first half of Tuesday’s defeat in Ukraine.
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