Olympiacos' Euroleague fate is out of their hands after they suffered a damaging defeat to Khimki in the Top 16, but Barcelona prevailed.
Khimki struck a major blow to Olympiacos' Euroleague play-off hopes and enhanced their chances of advancing by securing an emphatic 98-66 home victory on Thursday.
Three-time Euroleague champions Olympiacos' fate is now out of their hands, while Khimki occupy the fourth and final play-off spot in Group F with just one game remaining.
Petteri Koponen made a key impact from the bench, landing five three-pointers in a 21-point haul which came in the space of only 17 minutes. Alexey Shved claimed 19 points and James Augustine 18, as well as 10 rebounds, in an impressive display for the Moscow outfit.
Olympiacos were runners-up to Real Madrid last year, but face the prospect of failing to make it beyond the Top 16 stage this time around.
Khimki's victory ensured they are in fourth spot, while Barcelona are also well in the hunt for a play-off spot after seeing off Brose Baskets Bamberg 75-57.
Barca will be assured of progressing if they beat Zalgiris next week following a victory in which they took command in the first half, with Alex Abrines helping himself to 13 points and Joey Dorsey taking nine rebounds.
Lokomotiv Kuban moved a step closer to sealing home advantage in the play-offs by easing to an 81-60 home victory over Unicaja in Group E.
Kuban will be be at home in the last eight if Panathinaikos lose to Cedevita on Friday, as Crvena Zvedza are unable to catch them following their surprise 80-61 home defeat to Darussafaka Dogus.
Matt Janning and Malcolm Delaney scored 15 points apiece for Kuban, who ran away with it in the final quarter against a Unicaja side sitting bottom of the group.