Everton boss David Moyes has admitted Tim Cahill will not be fit for the start of the new Premier League season, while the brother of Joseph Yobo has been released from his kidnap ordeal.
The Australia international midfielder is recovering from a broken metatarsal and is due to head back to his homeland for a final appointment with his specialist.
Young striker James Vaughan is another working his way back to full fitness after consulting Dr Richard Steadman over his knee problem.
But Moyes had better news over Spanish playmaker Mikel Arteta, who is now back in full training following stomach surgery.
Moyes told the club's official website: ""Mikel is training with us again and that is a boost.
"We are pleased with the progress that he has made and there is an outside chance that he will be involved when we play Cambridge (on Saturday).
"James Vaughan is coming on all the time but it is a slow process with him. It is the same for Tim Cahill and I am not expecting him to be fit for the start of the season.
"He is going over to Australia to see the specialist for a last check but it is so far, so good."
The Scot added: "We've got a few injuries to deal with.
"Leighton Baines (ankle) and Tony Hibbert (knee) are in the crew that have had operations, too, don't forget. Bainesy is ahead of schedule but we also know that we have got to be careful with them."
Meanwhile, kidnappers have released the older brother of Everton and Nigeria defender Joseph Yobo after almost two weeks in captivity.
Norum Yobo was snatched at gunpoint with three other men on July 5 as they made their way home from a nightclub in Port Harcourt in Rivers State, Nigeria.
After 12 days of uncertainty, Norum's release was confirmed by John Ola Shittu, who manages Joseph's affairs.
Shittu told kickoffnigeria.com: "Yes, I can confirm to you that Norum has been released.
"He was released last night and he flew into Lagos this morning (Thursday) to meet his brothers. He is now at home resting and just trying to recover."