Champions League first knockout round, first leg:

• Barcelona 2 - Chelsea 1
• Man United 0 - AC Milan 1
• Porto 1 - Inter Milan 1
• Werder Bremen 0 - Olympique Lyon 3

Barcelona won the battle of the Spanish and Premier league leaders, coming from behind to beat Chelsea 2-1 in the first leg of their Champions League first knockout round first-leg tie at the Nou Camp in Barcelona.

Second-half strikes from Maxi Lopez and Samuel Eto'o countered a first-half own goal by defender Juliano Belletti after Chelsea were reduced to 10 men in the 56th minute when striker Didier Drogba [Images] was sent off.

Chelsea's was a classic counter-attacking goal made by winger Damien Duff against the run of play just past the half hour.

Duff had been ruled out as unfit only a day earlier by wily Chelsea coach Jose Mourinho but his speed on the break suggested his much discussed knee injury had never been too serious.

After concerted pressure by the home side, England's [Images] Frank Lampard [Images], an almost invisible midfielder for the first half hour of the match, supplied Duff with a pinpoint pass upfield.

Duff sped down the flank and aimed a cross at Drogba which a sliding Belletti could only poke past keeper Victor Valdes.

Frank Rijkaard's Barcelona were nearly caught again a minute later when Claude Makelele clipped the ball into Drogba's path from the centre circle. The striker raced clear and with just Valdes to beat bent an angled shot wide.

Drogba, in his first match after more than a month out with a thigh injury, undid his good work early in the second half when he was sent off for colliding rashly with Valdes, his second yellow card after a first-half booking for a bad tackle.

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It took Barcelona 11 minutes to take full advantage and with blue and red shirts bearing down on the Chelsea goal, substitute Maxi Lopez locked on to a pass from Eto'o and fired past Petr Cech.

Six minutes later Eto'o and Lopez combined again, the Argentine, signed from River Plate in the January transfer window, his cross-shot being seized upon by the African Player of the Year who made no mistake from close range.

For most match and even before Drogba's dismissal Chelsea were doing a holding job, stemming waves of jinking Barcelona runs from Ronaldinho [Images] on the right and Ludovic Giuly on the left, then from Lopez and Andres Iniesta.

Barcelona may rue their profligacy in front of goal after repeated chances went begging as Chelsea earned a valuable away goal for the return leg at Stamford Bridge on March 8.

By the last 15 minutes the London [Images] side were reduced to blocking, with every player behind the ball in a desperate rearguard action.

It was the first time under Mourinho that Chelsea have lost two games in a row, having gone down 1-0 at Newcastle United in the FA Cup on Sunday, but the Portuguese coach will be thankful the margin was only one goal.

Mourinho refused to make any public statements after the match and stopped his players from doing so. Chelsea issued a statement saying that they would make an official protest to UEFA [Images] about an incident at halftime, understood to be a conversation between Rijkaard and Swedish referee Anders Frisk.

Rijkaard appeared bemused when asked about the incident. "I cant' say what was upsetting Mourinho so much, he said.

"I spoke to the referee in a nice, friendly manner, maybe that's what started it but I don't understand it.

"I said 'hello, nice to see you' and something about the game, nothing else.

"I'm curious what Chelsea have to say about it. There was a lot of talk before the game and now there appears to be a lot after the game and I don't think that's a good thing.

"It's a surprise that after the game they have invented a story about something that didn't happen."

On the game, he said his match-turning decision to send on Maxi was straightforward.

"We were 1-0 down and we had to try everything to help us win and change our formation to take advantage of the fact that they had been reduced to 10 men so I opted to put on another forward," he said.

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