Yerry Mina is still a minimum of three weeks away from making his Everton debut after a relapse during his recovery from a metatarsal injury.
Everton signed Mina and Andre Gomes in a double deal from Barcelona on deadline day, despite knowing that the Colombian had fractured the fourth metatarsal in his left foot.
Marco Silva had hoped to have the Colombian available soon but Mina's agent and uncle Jair Mina confirmed to the media in his home country that further complications had delayed the defender's return from injury.
Silva confirmed in his press conference on Friday that Bernard had accidentally trodden on Mina's foot in training, aggravating his injury.
"Two days ago he [Mina] suffered an accidental stamp on his foot from Bernard," said Silva, quoted by Everton's official website. "It was painful and stopped him from training yesterday and today. We hope early next week he will start training again."
L'Equipe claims that Mina is now unlikely to play for Everton for at least three weeks. The earliest match in which he could make his debut is against Crystal Palace on October 21.
Silva is yet to settle on his preferred centre back pairing, having experimented with Ashley Williams, Mason Holgate, Phil Jagielka, Kurt Zouma and Michael Keane in that position already.
This uncertainty has cost Everton, who have won only one of their first six matches and are yet to keep a clean sheet. Whether Mina is the answer to their problems remains to be seen.
Everton signed Mina for £27m just eight months after he had joined Barcelona from Palmeiras. He only made six appearances for the Spanish champions before making the move to Goodison Park.
Mina scored three goals for Colombia at the 2018 World Cup, including an equaliser against England in the last 16.