Everton midfielder Morgan Schneiderlin will miss Saturday's derby clash with Liverpool and the trip to Manchester United next week, Ronald Koeman has confirmed.
The 27-year-old is struggling with a calf problem he picked up in the 4-0 victory over Hull City on March 18 but was pictured this week completing gym work in a bid to recover before the visit to Anfield.
However, manager Koeman says Schneiderlin will not face Jurgen Klopp's side and is unlikely to be fit enough for the match against old club United at Old Trafford next Tuesday.
"He's better now but still not available for the weekend," he told Everton TV.
"I don't think he will be available for Tuesday but we have good hope that he will be available for the Leicester City game."
The news is a big blow to Everton's hopes of a first derby win in the Premier League since 2010.
Full-back Seamus Coleman is out as a result of the broken leg he suffered in Republic of Ireland's World Cup qualifying draw with Wales, while centre-back Ramiro Funes Mori sustained a knee injury on Argentina duty.
Ireland international James McCarthy is also sidelined after he picked up a hamstring injury in the warm-up before that meeting with Wales, and Koeman has accused Martin O'Neill and the player himself of refusing to heed warnings over his fitness.
"The assessment of the Ireland medical team would be that it would be high risk for James to play. When asked to play he said he felt he was fit," he said at a media conference.
"In my opinion the Ireland manager in this instance was not protecting the player. He had only two days training for Ireland and broke down in the warm up.
"In my opinion he would need at least one full week of training with the team to be declared fit. I spoke to James, he needs to take responsibility.
"It is not the first time."