The Blues moved to within touching distance of the Champions League quarter-finals on Tuesday and eased the mounting pressure on manager Ancelotti with a 2-0 victory in their last-16 first leg at a frozen Parken Stadium.
The result kept alive their one remaining hope of silverware this season following a miserable few months that have seen last year's double winners all but surrender their Barclays Premier League title and crash out of the FA Cup.
It got better for Chelsea when Tottenham were beaten 3-1 at Blackpool, giving their London rivals the chance to reclaim fourth place in the league if they beat United on Tuesday night.
"We don't have to be happy for Tottenham's defeat, but it was good news for us," said Ancelotti, who urged his side to repeat their Copenhagen display against the Premier League leaders.
"Now we have to play against United and try and put in the same performance."
Source: PA
Source: PA