The People says Rooney was raging at an attack on him by outspoken Whelan at the height of the striker's troubles at Old Trafford.
In a typically straight-talking outburst, Whelan advised new United boss David Moyes to sell him. Rooney and his camp were fuming at Whelan's suggestion he was "lazy" and "not putting in a shift."
Rooney's livid advisers rang manager Owen Coyle to complain on the morning of the Community Shield between United and Wigan - and threatened to sue.
But then Wigan boss Coyle, sacked last week, said he would help defuse the diplomatic row by speaking to both Moyes and Whelan in the Wembley build-up.
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