But he has been advised by a physiotherapist to rest for three days.

O'Sullivan injured his lower back while having a massage at his hotel during last month's China Open and although he went on to capture the title at Mission Hills, his third of the season, the problem has apparently not gone away.

Even so, O'Sullivan contributed frame wins over Da Hai Lin and Hasimu Tuerxun as England began their defence with a 4-1 win over China on Saturday.

However, O'Sullivan has been advised not to play snooker for the next three days but hopes that intensive treatment will enable him to return to the team, alongside Stephen Lee and John Parrott, for Wednesday's clash with Northern Ireland.

In China, O'Sullivan, who contemplated withdrawal, explained: "She really cracked my back. It's all bruised up."

O'Sullivan's temporary absence has led to world number 11 Anthony Hamilton being called up as a late replacement.

And the 29-year-old from Nottingham, who himself missed the first two tournaments of the season with a broken wrist, is delighted to fill the breach.

"Obviously I am sorry that Ronnie can't play for England tomorrow but I'm more than happy to step in - even if it's only for one match. It's always an honour to represent your country."

Parrott, the skipper when England captured the title 12 months ago, will take over the captaincy for the Republic of Ireland tie.