James Rodriguez was the only Colombia player to miss training on Saturday, raising further doubts about whether he will be fully fit for the World Cup knockout match against England on Tuesday.
Rodriguez, who was top scorer four years ago, has been bothered by a calf injury since the start of the tournament in Russia.
He left the field in the 31st minute of Colombia's 1-0 victory over Senegal on Thursday night, but his injury has never been officially disclosed as the reason for the substitution.
Colombia still haven't clarified how serious the injury is and speaking before training on Saturday midfielder Carlos Sanchez and backup goalkeeper Camilo Vargas also didn't shed any further light on Rodriguez's progress.
"James is a leader, but I'm also sure that if James isn't there, there are others who can step in and make the difference," Sanchez said. "Each member of the team's squad is here to play and they have the experience."
Rodriguez missed two training sessions before Colombia's first group match against Japan and didn't start in the 2-1 loss. He was fit enough to play a full 90 minutes in the second match against Poland in the 3-0 win.
With Colombia facing England on Tuesday, the possibility that Rodriguez wouldn't be fit enough to play would be a major headache for coach Jose Pekerman.
"It's not a secret to anybody what James means for us, not only in football terms, but for the group. But I stand by what Carlos says," Vargas added. "At the level of the national team, everyone has the hope of giving their best.
"Whatever happens, all 23 players have that dream."
