Everton defender Yerry Mina is set to be out for eight weeks with an ankle injury suffered on the opening weekend of the Premier League season.
The Colombia international, 27, was forced off in the second half of the 1-0 home defeat by Chelsea on 6 August.
Fellow centre-back Ben Godfrey also fractured a leg in the 10th minute of that match.
Mina was not in Everton's squad for the 2-1 defeat at Aston Villa on Saturday.
He made only 13 league appearances last season in a campaign disrupted by injuries.
Manager Frank Lampard said Everton had enough cover at centre-back despite Godfrey being out for three months.
Lampard signed Conor Coady on loan from Wolves and former Burnley defender James Tarkowski on a free transfer in the summer.
He also has centre-backs Mason Holgate and Michael Keane in his squad.
