After a 3-3 draw at Old Trafford, the two clubs will meet again at Stamford Bridge just two days after their latest Premier League fixtures on Saturday.
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"These games are just too close to each other," he told reporters. "People have to realise they can't expect a great game of football because it is not possible.
"Normally on the second day your muscles are quite bad, but now we have to play at this certain time.
"It is a shame but we can't do anything about it because there are Champions League games in midweek and Chelsea are still in the Europa League."
Chelsea interim manager Rafa Benitez has also bemoaned the fixture congestion after he was forced to make eight changes to his side for the 2-1 loss to Southampton at the weekend.
"When you don't have one or two players you have to manage the squad," he said. "The day after a game you feel tired, two days after you feel even more tired.
"That is the reality. The second day will be really tough for everyone."