SARANSK, Russia, June 18 (Xinhua) -- Colombia superstar James Rodriguez is still doubtful for the team's opening match against Japan in the World Cup Group H actions, coach Jose Pekerman said on Monday.

"We are still waiting to see what the doctors will say on James," Pekerman said in a pre-match news conference on Monday. "We always wait until the very last minute before we decide. The World Cup is played after a busy season and it's true some players arrived here in Russia not feeling very well, so we need to be very careful about players' health."

Rodriguez, 26, is still recovering from a leg injury but expected to spearhead the best generation of Colombian players since the 1990s at this year's World Cup. He was the top scorer in Brazil World Cup 2014 with six goals in five matches.

"We have enough players for replacement. Our team is much richer and much stronger than in 2014," the coach added.

Colombia is grouped with Japan, Senegal and Poland. The Colombia vs Japan match will be held on Tuesday.