A solitary strike from Karim Bellarabi mid-way through the first-half proved enough for Bayer Leverkusen to get the edge on Sporting CP.
Die Werkself won 0-1 in Portugal, and will now be confident of progressing through to the last 16. It was the hosts' second defeat in their last 21 Europa League home games.
Both teams were willing to come forward in the early stages of the came, though Leverkusen were the better side.
Sporting's more measured approach with quick counters allowed early opening for Stefan Kießling and Julian Brandt, though their long range efforts were off target. Ömer Toprak had the first proper chance of the game, though he headed over.
Just as Sporting seemed to be getting a foothold, as Jefferson tested Bernd Leno from the edge of the area, Leverkusen took the lead. In his 400th game for the club, Kießling spread the ball wide to Tin Jedvaj. The Croatian wing-back whipped the ball into Bellarabi, and he calmly clipped the ball past the oncoming Rui Patricio.
The latter stages of half were a real struggle for both teams, who failed to get make any inroads after the goal. Despite the best efforts of the hosts, it was Leverkusen who went in with the lead - much to Roger Schmidt's delight.
Leverkusen confident after Semedo red card
Bayer began the second half on top and were unlucky not to be further ahead when Patricio made a smart save to deny Admir Mehmedi from Hakan Calhanoglu's pass. This prompted a double change from Jorge Jesus, bringing on Adrien Silva and Islam Slimani in a bid to finally spark life into his attack.
If anything, this left the visitors more space and they began to get more confident going forward. Kyriakos Papadopoulos headed two corners just wide in quick success, while Kießling felt he should have had a penalty when bundled into by Ruben Semedo.
The defender was sent-off soon after when he clattered into Bellarabi, leaving Leverkusen free to play down the clock. They could have extended their lead even further, however, as Patricio against denied Mehmedi before Bellarabi struck the post late on. Despite the missed opportunities, Schmidt's men are in a great position heading into the second leg.