Hwang Ji-woon scored as rock-bottom Daejeon beat Seongnam Chunma 1-0 while Daegu won 2-1 away to Jeju United. Choi Ho-jung and Hwang Soon-min scored Daegu's goals, with Yoon Bit-garam replying late on.
Daejeon's case still looks forlorn despite that result, however, as they languish four points adrift of the safety line and have only two games to play, compared to three for the rest of the teams still under threat.
Daegu are three points adrift of both Gangwon FC and Gyeongnam, but on equal games and with fixtures to come against both those sides.
In two largely meaningless Champions Group fixtures, Lim Sang-hyub's goal gave Busan I'Park a 1-0 win over Suwon Bluewings while FC Seoul and Incheon United drew 2-2.
Mauricio Molina gave Seoul the lead but they needed a last-minute Sergio Escudero strike to earn a point, quickfire goals from Han Kyo-won and Park Tae-min having taken Incheon ahead.