Bayer Leverkusen turned in an impressive performance to open their account in Champions League Group C and leave Benfica staring an early exit in the face.
Stefan Kiessling opened the scoring and Son Heung-min doubled the lead before Eduardo Salvio grabbed one back against the run of play.
But Hakan Calhanoglu swiftly netted another from the penalty spot to hand Leverkusen a 3-1 win and leave Benfica bottom of the group without a point.
Emir Spahic returned for the home side after being suspended for the weekend draw against Freiburg while Wendell also started in defence and Stefan Reinartz played the holding role in midfield.
Julio Cesar began in goal for Benfica and was called into action after five minutes as he saved Son's effort.
Leverkusen had begun on the front foot with Karim Bellarabi and Calhanoglu both trying their luck but missing the target before the former brought a save from Cesar.
Lars Bender went closer still to breaking the deadlock for the Germans when he hit the post from 12 yards in the 14th minute and it looked increasingly like a case of if, not when, they would take the lead.
Nicolas Gaitan showed his frustration and was booked for dissent following an offside decision and that was compounded when Leverkusen took the lead in the 25th minute.
Son's shot from distance was parried away by Cesar but Kiessling was on hand to turn home the rebound from close range.
Cesar then made another save from Bellarabi but Leverkusen were 2-0 ahead after 33 minutes and it was no more than they deserved.
Bellarabi and Bender combined down the right and when the former provided the cross, Son was there to provide the finishing touch.
Enzo Perez had a chance to grab a goal back from a corner shortly afterwards but his mis-hit shot was blocked away and Son should have had a second goal in first-half stoppage-time but fired wide when well positioned.
Maxi Pereira and Lima were brought on at the break by Jorge Jesus but his team remained on the back foot and Calhanoglu missed a sitter from six yards as the chance to make it 3-0 went begging.
Kiessling then missed the target and the impressive Son brought a save from Cesar as the Germans continued to press.
Benfica hit back against the run of play as Nicolas Gaitan found Salvio and the Argentinian produced a smart finish to reduce the arrears.
The Portuguese champions' joy was short lived, though, as Jardel brought down Kiessling in the next attack and Martin Atkinson pointed to the penalty spot.
Calhanoglu sent Cesar the wrong way and Leverkusen had restored their two-goal lead just after the hour.
The Germans continued to dominate in the closing stages with Calhanoglu and Son both bringing saves out of Cesar and they easily held on to take their first points in the group.