England are sweating on the availability of of second row Maro Itoje for tomorrow's Guinness Six Nations clash with Ireland at Twickenham, after he became unwell overnight.

Itoje will miss today's captain’s run at the stadium but England are "cautiously optimistic" that he will be available to take on Andy Farrell’s title rivals (4.45pm).

In a second blow to the squad on the eve of the game, forwards coach Richard Cockerill has tested positive for Covid and is now self-isolating.

Should Itoje be unable to play in tomorrow's game at Twickenham, Wasps lock Joe Launchbury would be the most likely to partner Charlie Ewels.

The 30-year-old was named on the bench, for what should be his first Test match since December 2020, having struggled with injury in the last year.

England had already been forced into changes from their win against Wales last time out, with hooker Luke Cowan-Dickie ruled out for the remainder of the tournament due to a knee injury, while number 8 Alex Dombrandt was only suited to a spot among the replacements, having had Covid-19 last week.

Ireland scrum coach John Fogarty said Itoje would be a major loss for England.

"He’s another experienced player, he’s a difficult character to deal with because he’s so involved – he tries to have lots of involvements in the game," Fogarty said of Itoje.

"He’s a huge strength of theirs. He’s a nuisance at times but he’s excellent. He would be a loss, of course.

"They’ve got some strength in depth and they’ve got some size; Launchbury is an excellent player, he’s got lots of experience and adds something different as well. But sure, he (Itoje) would be a loss."

Smiling, Fogarty added: "Let’s hope he’s all right."

England remain optimistic Itoje will be fit to feature, according to forwards coach Matt Proudfoot

"Maro was a little sick overnight so we're just giving him an opportunity to recover, but we’re really optimistic he’ll be all right," he said.

Additional reporting: PA

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