Chelsea manager Jose Mourinho raised the stakes for the second leg of the League Cup semi-final with a thinly disguised attack on Manchester United [Images] manager Alex Ferguson after the teams drew 0-0 in the first leg at Stamford Bridge on Wednesday.

Without naming him directly, Mourinho intimated the United manager had somehow influenced referee Neale Barry by walking down the tunnel with him at halftime.

"What I thought, what I saw, what I heard at halftime was important for me to understand a few things," said Mourinho, whose side were frustrated by Ferguson's side.

"We saw one referee in the first half and one referee in the second half. We saw dozens and dozens of free kicks in the second half. It was foul and then dive, foul and dive and only two minutes added on."

Asked what exactly he was suggesting, the Portuguese coach added: "What I'm suggesting is that the referee didn't walk alone to the dressing room at halftime, he should walk with the fourth official or the linesman, but there was somebody else with him.

"You only have to analyse the referee's performance in the first half and the second half, maybe one day when I'm 60 and I've been in this league for 20 years and I know everybody and everybody respects me, I will have this power."

United were also accused of having too much contact with match officials by former Tottenham Hotspur manager Jacques Santini in a league match last September.

League leaders Chelsea battered away at United in a pulsating semi-final, with Frank Lampard [Images] and late substitute Jiri Jarosik both having efforts cleared off the line while Eidur Gudjohnsen had a first-half effort disallowed for offside.

Wayne Rooney [Images], back after a three-match suspension, had United's best chances in the first half, while the visitors had two penalty claims turned down.

Despite failing to capitalise on home advantage, Mourinho said he was still confident Chelsea can stay on course for their first silverware in his reign by reaching the League Cup final in Cardiff on February 27.

"It's 50-50," he said. "They got the result they wanted tonight and I give them credit for that. If we go there and defend as well as they did tonight, albeit with a bit of luck, I will be very happy.

"The result wasn't fair tonight, but I accept it, because that's football."

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