Everton midfielder Tim Cahill is a doubt for the game against Manchester United after suffering an injury against Sporting Lisbon.
Cahill, who set up Steven Pienaar for the opening goal in Tuesday's Europa League win, was replaced just after the hour mark at Goodison Park.
He picked up a calf complaint and Everton boss David Moyes is waiting to learn the extent of the Australian's injury ahead of United's visit on Saturday.
"Cahill may have a calf strain, we're not sure of the severity yet," said Moyes.
Meanwhile, Toffees skipper Phil Neville was disappointed with his team's performance in the 2-1 success over Sporting in the first leg of the last 32 tie.
Pienaar and Sylvain Distin put Everton 2-0 up before the French defender was sent off late for conceding a penalty, which was converted by Miguel Veloso.
Neville said: "It was a flat performance. We were not at the same level as in the last couple of weeks and we did not pass the ball well enough.
"In Europe, you have to take a victory when it comes along, but we are definitely going to have to lift it for the second leg or we will be out of the competition.
"You think everything is going all right, then one bad mistake gives them an away goal and they leave with their tails up.
"We are so disappointed, but it is a lesson for how you have to keep your concentration in Europe."