. <p style="text-align: justify">First-stage champions Urawa Reds were forced to work for a 2-1 win against promoted Matsumoto Yamaga on Saturday to preserve their unbeaten record in this season's J-League.</p> <p style="text-align: justify">Goals from Yuki Muto and Shinzo Koroki secured the three points for last year's Japanese runners-up in their second-stage opener as Yamaga played with a back six in a bid to frustrate the visitors.</p> <p style="text-align: justify">"It was a bit of a tap-in goal but it went in and that's what counts," Koroki told reporters. "But the fact we ground out the result shows the mental strength we have this season."</p> <p style="text-align: justify">Meanwhile, 2014 champions and domestic treble winners Gamba Osaka needed a last-minute winner from Japan striker Takashi Usami to beat visiting Ventforet Kofu 2-1.</p> <p style="text-align: justify">Brazilian pair Elsinho and Renato were on target as Kawasaki Frontale opened the second half of the season with a 2-0 home win over FC Tokyo, who lacked a cutting edge in attack after they sold Japan international Yoshinori Muto to Germany's Mainz.</p> <p style="text-align: justify">The result was a tonic for Kawasaki, who were embarrassed 6-0 by Borussia Dortmund in a preseason friendly in midweek.</p> <p style="text-align: justify">"We got a lesson from Dortmund," said Frontale coach Yahiro Kazama. "It was precisely the type of training we needed."</p> <p style="text-align: justify">Twice champions Sanfrecce Hiroshima won a shootout away to Vegalta Sendai, prevailing 4-3 in northern Japan, while promoted Shonan Bellmare won 2-1 at home to Nagoya Grampus.</p> <p style="text-align: justify">Vissel Kobe were the day's biggest winners, smashing five unanswered goals past Shimizu S-Pulse, who finished the first stage bottom of the first division and look set for a relegation dogfight.</p> <p style="text-align: justify"><strong>By AFP</strong></p>