Chelsea interim boss Rafael Benitez believes that his side are a match for Manchester United but feels that playing for the second time in three days may affect his team.
The two sides square off in their FA Cup quarter-final replay at Stamford Bridge after the first game ended in a 2-2 draw at Old Trafford.
Benitez told the club's official website: "United are top of the table and we were better than them in the first game. We can compete, we have played some nice football, scored a lot of goals, but still, we have to be more consistent.
"We have offensive players with enough quality to create, but in some positions to find the balance is not easy.
"To play two games a week for four months is not easy to keep the team at the same level the whole time."
Chelsea have an excellent record in the FA Cup in recent years, winning the trophy four times in the past six seasons.
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