J-League Wrap: Sagan Tosu top after Urawa held
It looked as though Yoon Jung-hwan's men would have to settle for a draw against struggling Nagoya, but Kei Ikeda struck with seven minutes remaining to hand the hosts all three points.
That victory saw them move above Urawa, who needed a stoppage-time equaliser from Daisuke Nasu to rescue a point from a 2-2 draw at home to Vissel Kobe.
Urawa had gone in front in the 17th minute through Shinzo Koroki, but two goals in seven minutes midway through the second half from Hiroyuki Komoto and Shunki Takahashi turned the match around.
However, Nasu struck in the third minute of time added on to extend Urawa's unbeaten league to nine matches, stretching back to before the mid-season break.
One undefeated run that did come to an end was that of Kawasaki Frontale, who were thumped 4-1 at Kashiwa Reysol.
Third-placed Kawasaki had won all four of their previous matches since their return to action, but were stopped in their tracks by Reysol.
The home side moved ahead in first-half stoppage time through Kaoru Takayama, but Kawasaki replied immediately thanks to Kengo Nakamura.
That was as good as it got for the visitors, however, as second-half strikes from Masato Fujita, Takayama again and Leandro saw them suffer heavy defeat.
At the wrong end of the table, bottom club Tokushima Vortis led twice at home to Ventforet Kofu but were pegged back on both occasions to finish 2-2, while Omiya Ardija managed the opposite, twice coming from behind to secure a 2-2 draw away at Vegalta Sendai.
Kashima Antlers maintained their position in fourth spot, three points outside the AFC Champions League qualifying berths, with a 5-1 hammering of Sanfrecce Hiroshima, while Tokyo were equally convincing winners, 4-0 at home to Shimizu S-Pulse.
Elsewhere, Gamba Osaka saw off Yokohama F Marinos 2-0 at home, while struggling Cerezo Osaka went down 1-0 away to Albirex Niigata.