With Andriy Shevchenko already missing with a leg muscle injury, Didier Drogba had to be replaced at half-time during Saturday's 2-0 Premiership win away to Sheffield United after the Ivory Coast international hurt his right foot.

Mourinho is refusing to rule the pair out of Tuesday's match at the Nou Camp, but said both men could struggle to recover in time.

"Drogba was feeling a lot of pain and couldn't play on," Mourinho explained after goals by Frank Lampard and Michael Ballack gave the reigning Premiership champions their fifth straight win.

"I don't know if they will be fit, but for the first game against Barcelona earlier this season (which Chelsea won 1-0) we played without two keepers.

"Maybe we will have to play without both strikers this time."

With Chelsea sat at the top of their group and all but guaranteed a place in the last 16 of the Champions League after three wins out of three, Mourinho can afford to be light-hearted about his injury situation.

But he will be anxious his crocked forwards make quick and full recoveries as Chelsea's season reaches an important stage.

They had Portuguese keeper Henrique Hilario to thank for making their first trip to Bramall Lane in 13 years a successful one.

Hilario made a crucial penalty save from Danny Webber when the game was still goalless.

He was only playing because Petr Cech, the first-choice keeper, is recovering from a serious head injury while Carlo Cudicini has only just returned to training after being concussed in the same match as the Blues' number one at Reading.

Mourinho has been delighted with the way Hilario has performed for the first-team after keeping three clean sheets in four appearances.

He hinted he could play against Barcelona even though Cudicini was well enough to be on the bench against Sheffield United.

"Hilario played very well. He was amazing," said Mourinho. "The penalty save was crucial to the game.

"You never know what might have happened had Sheffield United, who were playing with such enthusiasm, had gone ahead.

"Carlo Cudicini trained with the group for the first time yesterday (Friday) and was available for the game. That's why he was on the bench. But Hilario is playing well and deserves his chance."

While Chelsea go from strength to strength, problems are mounting for Sheffield United manager Neil Warnock.

His struggling side have won just once in 10 top-flight games.

They face tough away games against Newcastle and Bolton, before hosting Manchester United, and Warnock insisted his players could not afford to be so wasteful from the penalty spot in the future.

"That's the third one we've missed now," said the Blades boss.

"We've got to start taking these opportunities. If it goes in Row E in The Kop I won't give anyone a rollicking.

"But we've taken some really poor ones lately.

"Just for once I would like to take the lead against teams like Chelsea instead of chasing them. It would have been lovely to put them under pressure."