Colombia coach Jose Pekerman said he was "extremely concerned" after their playmaker James Rodriguez was forced off through injury in their final World Cup group game against Senegal on Thursday.
Rodriguez lasted only 30 minutes in their 1-0 victory over Senegal before being substituted, putting his participation in their last-16 match in doubt.
"What I can say is that I am extremely concerned, it is a tough situation for my team," Pekerman told reporters after Colombia sealed their spot in the knockouts.
"It is not comfortable for us. He trained normally until today and he stayed on after practicing his free kicks and penalties. He was fully fit in training and in the last training session, no hint of injury. Right now, I do not know where he stands."
Colombia next face England on July 4, a match where they desperately need the last World Cup's Golden Boot winner.