Landon Donovan could be set to miss out on a Goodison Park farewell, David Moyes has revealed.
The American, whose loan spell ends after Saturday's visit of Blackpool, is suffering from flu.
Blues boss Moyes is already without the cup-tied Steven Pienaar and striker Nikica Jelavic who is suffering from athletic pubalgia, an inflammation of the pubic bone.
An ankle knock means Shane Duffy, the defender who this week received a first senior Republic of Ireland call up, may also be unavailable.
And Moyes admitted his injury concerns may not end there.
"We've got a few players who are going to be struggling tomorrow," he said. "But that's what happens at this time of the year.
"Landon's been great all round, he's contributed in every area, on the pitch and off the pitch he's fitted in really well, he's been a great ambassador for American football players and I'm sure everyone will look at him and say he's been excellent in the time he's been here. Unfortunately, he's got a bit of flu and he may miss the game. I'm not sure yet."
Jelavic, meanwhile, is yet to recover from the problem which prevented him making a home debut against Chelsea last weekend.
"Nikica has got pubalgia," said Moyes. "Most people who are in sport will know about it and it's an injury which, depending how severe it is, can keep you out for a short time or it can keep you out for a longer period. So it's something we're monitioring.
"He's feeling a bit better so we think it's going in the right way just now. But he won't be available for the game."
Jelavic himself admitted it is a blow to be sidelined so soon in his Blues career but believes Everton's upcoming fixture break could work in his favour.
The Toffees have no game next weekend due to Liverpool's participation in the League Cup final and will not play again until 3 March.
"It's frustrating for me believe me," Jelavic told evertontv. "But I'll keep fighting and I'm hoping in a couple of days I can be ready for training. It's a good thing for me that we have a two-week break after the cup so I can prepare myself well and be on the pitch and showing what I can do."
One piece of good news for Moyes was the return to action this week of Seamus Coleman.
With Donovan set to depart, the right winger's comeback is a timely one.
The 23-year-old Irishman came through 55 minutes in the reserves' 6-3 win over Newcastle on Tuesday and Moyes admitted he could now go straight into his starting line up.
"He'll be getting closer because of the numbers we've got available," he said. "It was great to have him back on Tuesday."
Moyes also confirmed the signing of Francisco Junior is yet to be completed.
The Blues have agreed a deal to bring in the midfielder as a free agent but the Guinea-Bissau born Portugal Under-21 international is still awaiting international clearance.