The 29-year-old has been an ever-present for the club this season but was notable by his absence at Goodison on Sunday, with Antolin Alcaraz starting alongside Sylvain Distin at the back.
When asked about Jagielka after the game, Roberto Martinez confirmed he is likely to miss the next month, though like Leighton Baines, his powers of recovery may mean he can return sooner.
After the New Year's Day trip to Stoke Everton play QPR in the FA Cup on the 4th January, Norwich on the 11th and West Brom away on the 20th. On paper at least, that is a relatively kind fixture list, meaning Jagielka's absence may not be too keenly felt.
However, the Merseyside derby at Anfield is pencilled in for Tuesday January 28th and that has to be Jag's target match to make a comeback.
Alcaraz's encouraging display against the Saints could also mean we don't miss Jagielka as much as first thought. The Paraguayan has been injured all season but has seemingly regained fitness at just the right time, putting in an assured display at the back.
Wigan supporters I have spoken too say he is an accomplished defender - when fit, which remains a big issue.
If he can keep himself on the pitch through these next few weeks, a notoriously tough time for all teams, then the consistency at the back - which has seen Everton concede just 18 goals in 19 games this season - will be successfully maintained.
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