The Suwon Bluewings climbed to third on the K-League table after a 3-1 victory over Incheon United on Sunday.
In front of their home fans at the Suwon World Cup Stadium, Seong-Hyo Yoon’s side took an early lead thanks to Hee-Ju Kwak’s strike on 19 minutes.
Macedonian forward Stevica Ristic doubled the advantage on the stroke of half-time.
Australian defender Eddy Bosnar was sent off for the hosts in the early stages of the second half and Incheon capitalised on their extra-man advantage as Jun-Jae Nam pulled a goal back in the 69th minute.
Substitute Tae-Goon Ha made sure of the three points for Suwon, with his injury-time effort enough for them to jump ahead of Ulsan on the table.
Elsewhere, Heyon-Chul Jeon and Seong-Jun Kim scored in the final 25 minutes for Seongnam in their 2-1 win over Daegu.
Matches between Busan I’Park and Pohang Steelers and Gangwon against Gwangju ended in goalless draws.