Women's World Cup star Linda Caicedo was "tired" when she went down clutching her chest in training, Colombia coach Nelson Abadia said, and may not play against Germany on Sunday.
The 18-year-old Real Madrid forward was at the centre of a health scare on Thursday when she stopped running and lay on the ground holding her chest.
Abadia on Saturday called it "an episode of tiredness, a bit of stress over her debut in a senior World Cup".
"It was just an episode and she is ok now," he added. "Linda has overcome the event.
"Whether she will play, we have 24 hours or a bit more to decide.
"She is a very important player for football and for us in our game plan."
Caicedo, who was diagnosed with ovarian cancer three years ago but made a full recovery, is a rising star of women's football.
She scored in Colombia's opening 2-0 win over South Korea in her World Cup debut this week.
Colombia face two-time former World Cup champions Germany in Sydney with a place in the last 16 in Australia and New Zealand in sight.
