Capello has apparently been irritated by Rooney's recent claims that some of his tactical ideas "got lost in translation".
Capello had already bitten on the subject once. Now, in the wake of England's Euro 2012 demise, and Rooney's poor performances after missing the first two matches due to suspension, the Italian has launched another salvo.
"After seeing the latest game, I think Rooney only understands Scottish," Capello told Italian radio.
"That's because he only plays well in Manchester, where Sir Alex Ferguson speaks Scottish."
Questions have been asked about Rooney's failure to reproduce his top form in major tournaments.
It is a fact that the 26-year-old has never come close to making the same impact he managed as a teenager at Euro 2004.
However, England's problems go much deeper.
An obvious failing in retaining possession was evident throughout England's time at the Euros.
And, whilst manager Roy Hodgson does not seem too concerned, captain Steven Gerrard admitted it was a problem that needed to be solved.
Others feel the amount of rest England's top players get is a factor.
And once again there have been calls for a winter break.
Senior football figures, including Ferguson, Arsene Wenger and Sven-Goran Eriksson, have been arguing for a mid-season halt to the English season for some time now.
Medical experts have previously added their voice to the calls, believing a break would reduce the number of serious injuries in the latter half of the season.
All four Euro 2012 semi-finalists enjoy a winter break but the huge competing interests in England have made it impossible.
TV contracts and a packed fixture schedule are the chief reasons put forward.
However, writing on Twitter in answer to a question about what would happen if the FA offered to scrap FA Cup replays, Premier League spokesman Dan Johnson said: "It would be an interesting discussion if that was seriously put forward."
As the FA have given no indication they want to make such a proposal, in all likelihood, the winter break debate will soon cease until the middle of next season, when a senior manager starts to talk about fixture congestion again.
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