Jonas late show sinks Villas-Boas on Portugal return
The Portuguese champions suffered a bitterly disappointing defeat to Porto last Friday and looked set to suffer further frustration against opponents coming into the match following the Russian Premier League's extended mid-season break.
But Zenit, led by ex-Porto boss Andre Villas-Boas and featuring their rivals' former star forward Hulk, tired down the stretch and a second yellow card collected by Domenico Criscito for a foul on Andre Almeida paved the way for their downfall.
The Brazil forward got up to thump a venomous free-kick wide and neither side came any closer to finding the breakthrough before referee Gianluca Rocchi sounded the half-time whistle.
Zenit midfielder Axel Witzel drove forward in the 52nd minute and Benfica keeper Julio Cesar was not entirely convincing as the Belgian's drive bounced awkwardly.
Kostas Mitroglou was largely feeding off scraps at the other end but managed to hustle former Benfica defender Ezequiel Garay out of possession to set up Gaitan - the captain's horribly skewed shot coming as a disappointment.
Zenit's Javi Garcia became the latest player to collect suspension inducing booking for handball before Gaitan forced Lodygin to repel his firmly hit shot.
But just as the weary visitors appeared to have weathered the storm, Criscito erred and - with Zenit seemingly distracted by their protests - Jonas pounced to nod home his 25th goal of the season.
Key Opta stats:
- Benfica have scored in each of their last nine European knockout games at home.
- This was Benfica 's first CL clean sheet in six games.
- Zenit failed to score in a European game for the first time in nine matches.