Chelsea, however, are adamant that none of their players were offered to Old Trafford in exchange, after Juan Mata and David Luiz were reported to be possible make-weights in the deal.

Ahead of Mourinho’s first match of his second spell in charge in Bangkok, Chelsea issued a statement, which read: “Chelsea Football Club can today confirm that yesterday it made a written offer to Manchester United for the transfer of Wayne Rooney.

“Although the terms of that offer are confidential, for the avoidance of doubt and contrary to what is apparently being briefed to the press in Sydney, the proposed purchase does not include the transfer or loan of any players from Chelsea to Manchester United.”

The stunning development comes less than 24 hours after the depth of Rooney's anger at comments made by United manager David Moyes became known.

With it looking increasingly like Rooney’s nine-year stay at Old Trafford is coming to an end, Chelsea have made their move.

Yet the Blues believe Mata and Luiz are key to their long-term plans and want Rooney to be part of Mourinho’s second coming.

Spain playmaker Mata and Brazil defender Luiz are absent from Chelsea’s Asia tour after being granted an extended break following the Confederations Cup.

It is clear Rooney is the number one target for Mourinho, who yesterday said he had no plans to sell any of his players.

That United should dismiss the offer so quickly is no surprise.

In recent weeks they have repeatedly insisted Rooney is not for sale, and the idea of selling to a domestic rival is particularly unpalatable.

Yet it is difficult to envisage how United can possibly hold that line right until the transfer window closes.

It increasingly appears Rooney’s position is untenable, with United fans likely to turn against their one-time hero.

And for Moyes, it represents a tricky situation given he is attempting to bolster his squad rather than weaken it.

Yet Rooney’s reaction to those comments given in a briefing during United’s stay in Bangkok last week has been the trigger for a further deterioration in the relationship between club and player.

Though it is thought Moyes did not wish the comments to come across as disparaging towards Rooney, that is exactly how they have been received, with the player – now back in Manchester for treatment on a hamstring injury – said to be “confused and angry” over their content.

The offending words were delivered to Sunday newspaper journalists during a briefing with Moyes in Bangkok last week.

Moyes said: “Overall, my thought on Wayne is that if for any reason we had an injury to Robin van Persie we are going to need him and I want as many options as possible.”

As far as Rooney is concerned, he is at the peak of his career and has no intention of playing second fiddle to anyone, or being reduced to the rank of a squad player.

With four Premier League titles and a Champions League winner’s medal to his name, the 27-year-old does not believe he has anything to prove at United.

Yet he feels as though he has been put on trial by Moyes at a time when he should be concentrating his efforts on recovering from the hamstring injury that saw him sent home from United’s pre-season tour within hours of landing in Thailand on Thursday.

After months of speculation about his future, and no statement of intent to stay from the player, it is now clear that unless there is some major repair work undertaken, Rooney will be leaving.

The manner of United’s response is the first major test for Moyes and chief executive Ed Woodward since they replaced Alex Ferguson and David Gill respectively at the beginning of the month.