Everton manager Roberto Martinez has confirmed that Tim Howard will be out of action for up to six weeks with a calf injury.
The 35-year-old goalkeeper sustained the injury during the Boxing Day defeat to Stoke City while taking a goal kick.
Joel Robles is expected to deputise for the American international after doing so in Sunday's 3-2 defeat at Newcastle United.
"Tim Howard will be out between five and six weeks with a calf injury," Martinez told reporters.
"I thought Joel was very calm against Stoke and did well against Newcastle, but we will assess whether we need cover."
Everton travel to Hull City on New Year's Day.