KAZAN, Russia, June 20 (Xinhua) -- Japanese players all expect a tough game against their next opponents Senegal following the opening win.

Japan and Senegal are now jointly leading Group H, after the Samurai Blue unexpectedly beat 10-man Colombia 2-1 while Senegal enjoyed an equally dramatic 2-1 victory over Poland. A further win would give either side a huge advantage for progressing into the knockout phase.

"In my opinion, the match against Senegal, which is also the second one for both sides, is the most important one for Japan in the group phase," Eiji Kawashima, Japan's goalkeeper and third-time World Cup player, told reporters after an open training at the FC Rubin First Team Training Ground.

He added that the Senegalese have some unique qualities, including including individual player' abilities, which the Samurai Blue should be cautious about.

"We've watched the video footage of Senegal players. They are such a strong team," said 31-year-old defender Yuto Nagatomo.

"Their speed and physical strength are something that I have expected, but (what stood out) are their discipline and strong defense as a team," said the Galatasaray defender.

"They moved as a connected unit, with every piece interlocking," he added.

27-year-old midfielder Hotaru Yamaguchi said that though they are still enjoying the opening win, everyone now is preparing for the next match.

For him, what he is focusing now is thinking of how to handle the fact that many Senegal players are tall and fast

Japan is to play Senegal on Sunday and Poland on June 28. According to FIFA, Japan are ranked 61st in the world, well below Senegal (27), Colombia (16) and Poland (8).