Ireland's Rob Kearney in training© Charles McQuillan

Ireland are taking no chances with full-back Rob Kearney's World Cup fitness.

Simon Zebo deputised at full-back in Saturday's 21-13 defeat to England at Twickenham, Kearney sitting out despite being branded fit for selection.

The 29-year-old Leinster star suffered a bruised knee in training last week, but head coach Joe Schmidt said he had remained available for the game.

Instead Ireland opted to hand winger Zebo another run at full-back in preparation for the 25-year-old covering Kearney during the World Cup.

"Rob Kearney will do moderated training in the first part of this week," an Ireland injury update statement read.

Zebo struggled positionally against England, Anthony Watson catching him out for the second of the hosts' two first-half tries.

Ireland base much of their tactical kicking attacking game around Kearney's prowess, leaving Kiwi boss Schmidt refusing to take any risks in training this week.

Wales fielded first-choice full-back Leigh Halfpenny for Saturday's 23-19 victory over Italy, but the Toulon star suffered potential knee ligament trouble and is now a huge World Cup doubt.

Ireland's ultra-cautious approach to Kearney's situation at the start of this week may well have been coloured by the misfortune that struck Wales and Halfpenny at the weekend.

Ireland have confirmed scrum-half Conor Murray continues to follow the return-to-play protocols after suffering concussion against England.

Schmidt is confident Murray will be fit for Ireland's World Cup opener against Canada in Cardiff on Saturday week.

Johnny Sexton and Zebo both limped out of the closing stages of Ireland's defeat in England, but Schmidt revealed their only issues as cramp on Saturday - and that was backed up by Monday's injury bulletin.

"Johnny Sexton and Simon Zebo suffered cramp towards the end of the game against England and were removed as a precautionary measure," it added. "Both are feeling no ill-effects and trained today."

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