Folarin Balogun has reportedly failed his medical ahead of a prospective move from Monaco to Everton.
The two clubs had agreed a transfer fee ahead of a £38.5 million deadline day move.
However, the deal is now in real jeopardy following reports from journalist Fabrice Hawkins that Balogun has not passed the necessary medical tests.
Everton's medical team believe the USA international is not fully fit, while Monaco are insistent that there are no issues with the player.
Balogun had also agreed personal terms but the medical issue is now a concern for all parties.
There is a possibility that Everton may seek a drop in price but it is unlikely that Monaco will want to budge on the deal.
Balogun enjoyed a standout 2026 World Cup in his home country and his potential arrival on Merseyside has excited Everton fans over the last couple of days.
The deal is not completely dead in the water yet, but time is running out for the two clubs to agree a compromise.
