Antalyaspor needed to at least match the result of fellow strugglers Kayseri Erciyesspor to keep their survival hopes alive but suffered a 2-1 home defeat to third-bottom Elazigspor.
And Erciyesspor's 1-0 win over Gaziantepspor condemned Fuat Capa's side to life in the second tier.
Lamine Diarra had put Antalyaspor in front but Batuhan Karadeniz's double secured victory for Elazigspor, who saw Fabio Bilica sent off in the latter stages.
The win was big for Elazigspor's survival hopes as they moved to within two points of safety.
Erciyesspor's triumph against Gaziantepspor also ended Kayserispor's prospects of staying in the top flight, despite an impressive 4-1 win at Eskisehirspor.
Sefa Yilmaz, Pablo Mouche, Diego Biseswar and Marcio Nobre scored for the victors but although they moved off the bottom as a result, their win ultimately meant little.
Rizespor and Konyaspor each benefited from late goals to claim a share of the spoils against Sivasspor and Karabukspor respectively, but both sides are now only four points above the bottom three.
Godfrey Oboabona scored a 90th-minute equaliser to earn Rizespor a 1-1 draw after Hakan Arslan had seemingly given Sivasspor the points a minute earlier, while Djalma and Theofanis Gekas each struck in the final 15 minutes as Konyaspor came from 2-0 down secure a 2-2 stalemate.
Fenerbahce may have already clinched the title but their poor form continued as Akhisar Belediyespor secured a shock 3-1 success.
Brazilian attacker Bruno Mezenga was the star for Akhisar, scoring a double to take his tally for the season to 11.
Meanwhile, Galatasaray stayed ahead of Besiktas, who beat Kasimpasa 2-1, in the race for the final UEFA Champions League spot as Umut Bulut capped a remarkable comeback with a 90th-minute strike to ensure a 3-2 triumph over Genclerbirligi.
Elsewhere, Bursaspor played out a 2-2 draw with Trabzonspor.
