In fact Chelsea FC did relatively little, but what they did do they did it well. Defend & counter-attack while Barcelona played their "patented" ball control style that increased along with frustration as the match went on & they could not score a goal.
Take these statistics, 7 clear chances for Barcelona, including the bar & the post, to one real chance to Chelsea that was the winning goal.
The first half saw Alexis hit the bar early, Cesc get his ball cleared off the goal-line by Andy Cole, multiple chances missed by Barcelona & the Chelsea FC goal in the last minute of the half ( 47th min ) by DROGBA from an excellent counter-attack from a midfield loss from Messi.
The second half saw Barça try everything, but they kept "crashing" into the Chelsea defensive wall, a fabulous Peter Cech save from a Puyol header flick-on & a post in the last moments from Barça sub Pedro. Just one of those Football nights for Barça & a grand evening for Chelsea were their match strategy worked out to perfection.
Now its off to Barcelona & the "Camp Nou" in 6 days for the 2º leg game where I still see Barça favourite as I didn't really see anything spectacular from Chelsea. Said all this, it is Chelsea which has the goal advantage & not Barça, & anything can happen in Football.
Great match ahead in all cases, not to be missed.