Jagielka was on the point of returning to training after rupturing a cruciate ligament against Manchester City last April. But now he has been booked in for surgery that will keep him out for up to six weeks more, says the Daily Mail.
Manager David Moyes said: "He was a bit down when he heard about it because he was due to start light training this week, but he is on the road to recovery now and feeling brighter. Even if it does take six weeks, that's still a pretty good recovery, as it's often seven months or so after a cruciate. It's just a little setback. Joe Cole had the same thing and he is back playing now."