The visitors started shakily, as Moussa Niakhate lost the ball to David Miculescu on the edge of his own box. The attacker then rounded goalkeeper Lucas Perri, but could only send the ball wide from a tight angle.
It was then Perri’s time to shine, as he first tipped Malcom Edjouma’s aerial effort over, before producing a stunning save from point-blank range as Siyabonga Nguezana swooped in with a diving header.
From there, Lyon started taking control of the first half, as Georges Mikautadze’s strike deflected wide and from the resulting corner, the Georgian’s near-post flick produced a reaction save from Stefan Tarnovanu’s outstretched leg.
Mikautadze wasn’t put off though, and produced a brilliant looping cross that set up the opening goal of the game on the half-hour mark, as Nicolas Tagliafico’s downward header at the back post could not be stopped by the sliding Nguezana.
Despite some early FCSB pressure, it was Lyon who looked more likely to double their lead in the second half.
Mikautadze was a constant threat, and his left-footed curler was heading towards the top corner before being stopped by Tarnovanu’s glove.
However, the hosts found an equaliser against the run of play, as Risto Radunovic crossed to the back post for substitute Alexandru Baluta, who calmly controlled the ball before lashing into the net.
That did not trouble Lyon though, as with just five minutes to go, their own substitute Malick Fofana netted his fifth goal in Europe this campaign by neatly placing the ball into the bottom corner after it fell kindly to him in the box.
In a chaotic end to the match, FCSB were the width of the crossbar away from equalising again, as Joyskim Dawa’s close-range header from a corner was brilliantly stopped by Perri.
The goalkeeper then quickly launched the ball forward, and Fofana was in on goal.
The teenager calmly slotted past Tarnovanu to give Lyon a two-goal advantage ahead of the second leg, while also maintaining their unbeaten H2H record against FCSB (W4, D1) in the process.
Flashscore Man of the Match: Malick Fofana (Olympique Lyonnais)