Suwon Bluewings lost their hold on top spot in the K-League after losing 2-0 at Pohang Steelers.
A spectacular free-kick from Kim Jae-sung after 19 minutes put Pohang in front and Shin Young-min sealed the win with a fierce half-volley from the edge of the area with just three minutes remaining.
It was enough to put Pohang in third place on goal difference, while Suwon, who thrashed Shanghai Shenhua 4-0 in their midweek Asian Champions League clash, slipped into seventh after dropping their first points of the season.
``We were defeated all in all areas,'' said Suwon coach Yoon Sung-hyo. ``The players did their best but are not in the best of condition. Still, this is a very difficult fixture and the start we have had to this season is not bad at all.''
Sangju Sangmu replaced Suwon at the summit after a 3-2 win against Seongnam Ilhwa Chunma. Sasa Ognenovski got his first goal of the season for the continental champions but could not prevent Sangju from taking three points thanks to a brace from Jang Nam-seok and a Kim Jung-woo goal.
K-League champions FC Seoul are still searching for their first domestic win despite collecting maximum points from the opening two games of the 2011 AFC Champions League. The capital club crashed to a 3-0 defeat at Chunnam Dragons and are languishing in 15th place.
Jeonbuk Motors made it two wins out of two by coming back from two goals down to thrash Busan I'Park 5-2 . The 2006 Asian Champions League winners are in fifth while Jeju United, who won 2-1 at Melbourne Victory in midweek, defeated bottom club Gangwon FC 1-0 to move into fourth.
Elsewhere, Ulsan Horang-I defeated Gwangju FC 2-1. Daejeon Citizen continued their good start to the season with a 2-0 win at home to Gyeongnam FC while Incheon United were held to a 1-1 draw by Daegu FC.