Defending champions Real Madrid were dumped out of the Euroleague on Tuesday, courtesy of a third successive loss to Fenerbahce.
Real had stood on the brink of elimination on three previous occasions this season, only to claim much-needed wins.
However, Pablo Laso's men were unable to pull off another rescue act this time around as Fener - who continue to overcome the injury-enforced absence of Jan Vesely - triumphed 75-63 in the Spanish capital to open up an unassailable 3-0 series lead.
Bogdan Bogdanovic top-scored for the visitors with 17 points, all of which were collected in the second half, while Ekpe Udoh contributed 15 points and 12 rebounds.
Fener will now play in the Final Four for a second successive year, while Laboral Kutxa also booked their place in the season finale - for the first time since 2008 - by beating Panathinaikos once again to sweep their series 3-0.
An 84-75 victory for Laboral in Athens ensured Dimitris Diamantidis ended his Euroleague career on a losing note, the much-decorated Panathinaikos captain having already announced this will be his last season.
With CSKA Moscow having qualified for the Final Four on Monday, only one place remains up for grabs.
Barcelona moved into pole position to claim that spot, opening up a 2-1 lead over Lokomotiv Kuban with an 82-70 triumph at Palau Blaugrana. Alex Abrines starred for Barca with 25 points.