Kostas Katsouranis' goal earned Panathinaikos a 1-0 victory over Sturm Graz to move them within touching distance of a place in the last 32 of the Europa League.
The Greece midfielder struck in the second half as the visitors claimed their third win in Group F, ending Sturm's faint hopes of progressing to the knockout stage.
A point against Galatasaray in two weeks will be enough to send the Greeks through to the next round.
Pana were looking to complete a group double over Sturm having carved out a 1-0 result in Athens two weeks ago.
And they showed early promise at the Stadion Graz Liebenau with Dimitris Salpingidis curling an effort narrowly wide in the 12th minute.
Sturm continued to find life difficult as the half wore on and goalkeeper Christian Gratzei had his palms warmed by a cross-shot from Gilberto Silva after 27 minutes.
Gratzei was tested again moments later by a strike from Katsouranis which the keeper claimed with a safe pair of hands.
Sturm had to wait 36 minutes for their first chance from midfielder Daniel Beichler, but visiting keeper Alexandros Tzorvas was equal to the challenge.
Samir Muratovic gave Pana more of a scare five minutes before the interval with a 20-yard bullet which just cleared the crossbar.
And Gratzei continued to be called on at the other end, ensuring the scores were level at the break by punching clear Salpingidis' dipping shot.
Beichler had another effort for Sturm as the hosts began the second half strongly, firing wide of the mark from 10 yards.
But Pana soon began to push forward again and Gratzei saved shots from Junior Simao and Katsouranis as the Greeks searched for the opening goal.
Loukas Vyntra wasted another chance for the visitors, drilling left footed over the bar from just outside the area, and it looked to be turning into a frustrating night until Katsouranis finally got the goal they deserved after 71 minutes.
Sebastian Leto swung in a cross for the unmarked midfielder, who stabbed the ball home from a few yards out.
Djibril Cisse could have added a second nine minutes from time but his right-footed strike was superbly tipped around the post by Gratzei at full stretch.