The England hopeful was set to be released from hospital today but could miss the rest of the season.

On-loan winger Vladimir Weiss is also absent as the Slovakian cannot face his parent club.

Andy O'Brien (thigh) and Fabrice Muamba (ankle) are both doubtful through injury while Gavin McCann and Ivan Klasnic remain sidelined.

Provisional squad: Jaaskelainen, Steinsson, Knight, Robinson, Gardner, Cohen, Taylor, M Davies, Wilshere, Muamba, Lee, K Davies, A O'Brien, Al Habsi, Samuel, Basham, Elmander, Ricketts, Holden.

Cahill is due to be released from hospital today after being kept in since Saturday.

Coyle said: "It is a severe blow for the boy but our main concern is his welfare. We have to make sure Gary is fit and well.

"He will miss the next few months, it might be for the rest of the season, we will hear from the specialist later.

"The clot needed to be resolved and in doing that you need the medication. It follows you can't play.

"As disappointed as we are, at 24, Gary has a marvellous career ahead of him. I believe he would have made the World Cup for the summer but we have to make sure first of all he recovers from this blood clot."