Didier Drogba scored a crucial stoppage-time winner at the end of the first half to defeat Pep Guardiola's Barcelona side 1-0 at Stamford Bridge, capping a fantastic defensive display for the English side.
Despite heading into the match as underdogs, Roberto di Matteo's side produced a gutsy performance to put themselves in control of the tie. Barcelona dominated possession, limiting their opponents to only one shot on target, but could not find find a way past a resilient defence and in-form Petr Cech.
Pep Guardiola opted to partner Carles Puyol with makeshift centre-back Javier Mascherano whilst Cesc Fabregas was drafted in to an all-Spanish midfield.
La Blaugrana started brightly, switching the ball to either flank before trying to find any form of penetration through the Chelsea defence. Alexis Sanchez was the closest to opening the scoring when he latched onto an Andres Iniesta through ball but saw his impudent chip strike the crossbar with Cech stranded.
Barcelona continued to fashion chances and Cesc Fabregas forced two excellent stops from the Chelsea rearguard, first being denied by Cech with a near-post drive from the corner of the box before Ashley Cole cleared off the goalline after the Spanish midfielder had dinked the ball over the goalkeeper.
The Chelsea back four, shielded by an impressive midfield duo of Raul Meireles and John Obi Mikel, thwarted Barcelona's attacking play time and time again, delivering the ball to the Ivorian forward Drogba, whose brillant performance was overshadowed by over-dramatic antics on and off the ball.
However, he proved to be Chelsea's hero in the second minute of additional time in the first period. Frank Lampard dispossessed Lionel Messi inside the Chelsea half before playing a cross-field pass to the onrushing Ramires who surged into the penalty box and squared for the waiting Didier Drogba who smashed the ball home in typical fashion, sending the home crowd into raptures. One shot, one goal. It was a devastating counter-attack which concluded Chelsea's effective gameplan and barely gave their opponents time to restart, leaving the usually humble and calm Barcelona boss bemused.
The second half followed a similar pattern with Barcelona carving the majority of the chances, forcing Chelsea deep inside their own half and defending as if their season depended on it. Adriano was the first to test the Chelsea goal, skipping past Lampard before sending a curling right-footed effort towards goal which Cech palmed away.
Sanchez then had a glorious chance to level the scores after he beat the offside trap to latch onto Fabregas's beautiful scooped pass but he could only strike past the post when he should really have done better. It was not one of the Chilean's better nights and he was duly dismissed, in place of Pedro.
Drogba continued to cause problems up front with his bullish approach and nearly set up international teammate Salomon Kalou but he fired over the bar from six yards after he failed to control a searching long ball.
As the clock ticked down, Barcelona's desperation kicked in and Chelsea, buoyed on by a fantastic home support continued to frustrate the reigning European champions with a series of well-timed blocks and organised defending.
However, their good work was nearly undone in the 87th minute when Messi's clever freekick was flicked on by Puyol but Cech reacted quickly to pull off a world class save, tipping the ball around the post for the umpteenth time in the game.
Late drama was to follow in the final minute of the match however as John Terry's clearance found Pedro on the edge of the box and the Spanish winger sent a curling first-time effort past a despairing defence but struck the post and as the ball fell to Sergio Busquets six yards out, the tall defensive midfielder could not quite sort out his feet and he sent the ball high over the crossbar, to the relief of the Chelsea fans, who had their heart in their mouths once again.
However, miraculously they managed to cling on to a quite superb 1-0 home victory, giving them a slender advantage heading into next Tuesday's return leg. If the first encounter is anything to go by, we could be in for another classic.