Besiktas qualified for the knockout rounds of the UEFA Champions League for the first time in the club's history thanks to an entertaining 1-1 draw at home to Porto.
The Turkish champion knew any positive result would confirm its historic progression, and top spot in Group G, but it had to come from behind at a typically raucous Vodafone Park.
Porto took the lead against the run of play after 29 minutes, Alex Telles combining with Ricardo Pereira from a set piece to tee up Felipe for a stunning first-time strike.
Besiktas scored a deserved equaliser before the interval, Cenk Tosun doing brilliantly to set up attacking partner Anderson Talisca for a straightforward close-range finish.
Both sides had chances to win the game in the second half, Ryan Babel hitting the crossbar with a speculative strike and Ricardo Pereira wasting a fine opening, but the points were shared.
Porto will host Monaco on the final Matchday, the Portuguese side not yet sure of its place in the next round despite having seven points on the board.
Besiktas almost opened the scoring after six minutes when an inviting cross from Ricardo Quaresma on the right was marginally too high for Tosun and Talisca.
Babel, who wrapped up Besiktas's 3-1 win at Porto earlier in the group, then forced Jose Sa into an unconvincing save with a swerving effort from long range.
But despite the hosts' strong start in an intimidating Istanbul atmosphere, the crowd was silenced after 29 minutes.
A quick free-kick was fed to Ricardo Pereira, the winger's low cross thumped home by Felipe's first-time strike that gave goalkeeper Fabri no chance.
Quaresma burst in behind the Porto defence to force a smart stop from Sa as Besiktas responded well, but the visitors should have doubled their lead when Vincent Aboubakar blasted Ricardo Pereira's cross over the crossbar.
That miss was swiftly punished as Besiktas levelled five minutes before the break.
Babel's flick freed Tosun, the striker finding space with an impudent touch over Maxi Pereira's head and showing great awareness to square for Talisca to roll the ball into the open goal.
Besiktas maintained their dominance after the interval and Babel was inches away from scoring a sensational goal after 57 minutes, cutting inside and thudding a 25-yard drive against the crossbar.
Sa then turned away a powerful Quaresma drive and Porto spurned a glorious chance moments later, former Besiktas striker Aboubakar bursting into the box to set up Ricardo Pereira, who refused to shoot with his left foot and instead bent a poor effort wide with the outside of his right boot.
Both teams appeared to settle for a draw in the closing stages, leaving Besiktas to celebrate a historic night, while Porto face a nervy matchday six clash with defending Ligue 1 champion Monaco.