Benfica came from a goal behind to beat Atletico Madrid 2-1 at the Vicente Calderon and go top of Group C.
It was a clinical display of counter-attacking football from the Portuguese champions, who had gone behind after 23 minutes courtesy of an Angel Correa goal for Atletico.
However goals from Nico Gaitan and Goncalo Guedes were enough to seal a victory that sees Benfica maintain their 100 percent start and leapfrog their Spanish counterparts at the top of the group.
Atletico took the lead when Correa latched on to a sublime first-time volleyed pass from Antoine Griezmann and he clipped the ball beyond Julio Cesar in the Benfica goal.
Jackson Martinez was proving himself to be a constant menace to the Benfica defence, just as he had been in his Porto days, but Cesar pulled off a string of reflex saves to deny the Atletico striker in an intriguing personal battle.
Benfica levelled the match, however, after 37 minutes when Argentinian playmaker Gaitan got on the end of a hopeful cross into the box and fired a venomous left-footed strike beyond Jan Oblak.
Guedes completed the comeback and put Benfica in front after 51 minutes. Gaitan led the charge on a slick counter-attack before crossing for the 18-year-old striker to slide in at the back post and cushion a delicate finish beyond Oblak.
The Spaniards continued to push forward to find the equaliser, but it was Benfica who looked the more likely side to score on the breakaway, with the excellent Gaitan playing a pivotal role.
At the other end, the Portuguese defence was expertly marshalled by veteran centre-half Luisao, who made a series of crucial tackles and interceptions to maintain his team's advantage.
Atletico manager Diego Simeone had a final roll of the dice with 10 minutes left by introducing Fernando Torres, but the former Chelsea man failed to net what would have been his 100th goal for his boyhood club as Benfica silenced the Calderon to emerge victorious.