Ferguson laments 'unbelievable' Cech save

Trailing 1-0 to Demba Ba's magnificent volley early in the second half, United looked poised to equalise in the 61st minute, only for Cech to produce a stunning stop to repel Javier Hernandez's close-range header.

It was to prove the closest the visitors came to forcing extra time, with substitute Robin van Persie lifting a pair of late chances over the crossbar.

"You have to say Cech's save from Chicharito was unbelievable," Ferguson told United's in-house television channel, MUTV.

"You need a bit of luck in the cup. He made a similar save in the first game (a 2-2 draw on March 10) from one of his own defenders.

"That was disappointing for us in terms of getting a little break. To be honest with you, I thought we were too rushed in that second half. We just lacked a bit of composure to create the proper openings."

Defeat leaves United with only the Premier League title race to focus on, and having already established a 15-point lead over Manchester City, there seems little potential for drama in the season's closing weeks.

Ferguson had spoken of his eagerness to see United triumph in the FA Cup for the first time since 2004, and he was unusually critical of his players after the game.

"Of course they are down, because they know they can do better," he said.

"I thought over the 90 minutes only Antonio Valencia reached the standard we expect of them.

"Phil Jones did for a good part of the game, of course, and David de Gea did well, but in terms of the 90-minute performance, Antonio Valencia was the only one."

The only negative note for Chelsea at Stamford Bridge was an injury sustained by left-back Ashley Cole, who appeared to hurt his hamstring as he chased Danny Welbeck mid-way through the first half.

Chelsea interim manager Rafael Benitez confirmed he would be out for around a fortnight, casting into doubt his participation in the semi-final against Manchester City at Wembley Stadium on April 14.

"With this kind of injury, it'll be at least two weeks," said Benitez.

In a lighthearted reference to Chelsea's congested calendar, he added: "That means for us, about 20 games or so."

Benitez is also currently without Gary Cahill, who has a knee problem, and the Spaniard revealed that the centre-back is likely to be sidelined for "another 15 days at least".

Despite the injuries to his two England defenders, Benitez says his side are poised to complete a "great season".

Benitez has faced opposition from Chelsea's fans ever since replacing the sacked Roberto Di Matteo in November, while the club's bid for Champions League qualification was compromised by a 3-1 defeat at Southampton on Saturday.

However, they have reached the FA Cup last four for the sixth time in eight years and also remain in contention in the Europa League, with the first leg of their quarter-final against Rubin Kazan due to take place on Thursday.

Although competition for a top-four finish in the Premier League remains intense, Benitez believes his side are ideally placed.

"I said before, the race for the top four will be until the end of the season," he said.