Everton have revealed that John Stones and Phil Jagielka will miss Saturday's pre-season friendly against Barnsley at Oakwell due to injuries.
The club's international players will feature for the first time since rejoining the squad, but two of their senior defenders will be absent.
It is unclear when Jagielka will be fit to play, but Stones could make an appearance in Tuesday's friendly against MK Dons.
Ross Barkley, Seamus Coleman, James McCarthy, Ramiro Funes Mori, Shani Tarashaj and Aiden McGeady are all expected to get minutes under their belts against Barnsley.
"We have the players back from the Euros and they will play 45 minutes and that is good because they need to work," manager Ronald Koeman told EvertonTV.
"It is always tough against English teams, we need those kind of friendlies to prepare for the Premier League season.
"For them to play a Premier League team is a nice challenge for them to look forward to. It's not always the result that is the most important thing - what you like to see is the team improving technically and physically."
Meanwhile, Stones's future remains uncertain amid reports that the centre-back is in talks to join Manchester City.