They were helped by the fact that Yokohama went down by the same scoreline at Omiya Ardija.
Shinzo Koroki's strike just after the hour mark lifted Urawa past Albirex Niigata and up to second in the standings, closing in on Yokohama after Daigo Watanabe's goal three minutes before half-time condemned them to defeat at Omiya.
Sanfrecce Hiroshima slipped a place to third after losing 2-1 at home to FC Tokyo.
Kazuma Watanabe bagged both goals for the visitors, the second nine minutes from time after Hisato Sato looked to have salvaged a point for the hosts.
Kashima Antlers climbed to fourth on the back of a 3-1 home triumph over Kashiwa Reysol. Junior notched a double after Yuya Osako had opened the scoring, with Masato Kudo's second-half strike not enough to get Kashiwa back in contention.
Fifth-placed Cerezo Osaka and Kawasaki Frontale battled out a goalless draw.
Shimizu S-Pulse held off a late fightback from bottom-of-the-table Oita Trinita to secure a 3-2 away win.
Taisuke Muramatsu and Genki Omae scored just before half-time to put the visitors in the ascendancy and they looked to be cruising when Toshiyuki Takagi stretched their advantage in the 63rd minute before substitute Yasuhito Morishima netted twice to set up a nervy ending.
Patric equalised four minutes from time as Vantforet Kofu drew 1-1 at second-bottom Jubilo Iwata. Hiroki Yamada had put the hosts ahead in the 75th minute.
Third-bottom Shonan Bellmare picked up only their fifth win of the campaign with a 3-2 home success against Vegalta Sendai.
Tsuyoshi Shimamura opened the scoring just after the half-hour mark and restored his side's lead just before the hour after Rodrigues Wilson had levelled. Wellington extended the hosts' lead after 64 minutes before Wilson's second goal of the game - from the penalty spot - reduced the deficit but Shonan held on.
Kota Mizunuma equalised five minutes into the second half to earn Sagan Tosu a 1-1 draw against Nagoya Grampus Eight, who had taken the lead 10 minutes before the interval through Takahiro Masukawa.