Ulsan Hyundai lost further ground to the K-League's top two after a 1-1 draw at home to Daegu FC.
Brazilian striker Rafinha put Ulsan ahead after 51 minutes but
The result means Ulsan is now nine and eight points behind leader FC Seoul and Jeonbuk Motors in second place respectively.
Chunnam Dragons slipped to the bottom of the table after a thrilling 4-3 loss to Pohang Steelers.
But Pohang hit back after the interval and goals from
Daejeon Citizen took advantage of Chunnam's defeat as its 1-1 draw with Gyeongnam moved it above the Dragons on goal difference.
Gyeongnam took the lead through Ii Rok Yun's 16th-minute strike but
K League Classic
Pohang Steelers opened up a five-point advantage at the top of the K League Classic thanks to a 3-2 victory at Jeju United.