Alex Ferguson has dismissed claims he axed Roy Keane from Manchester United's Far East tour for disciplinary reasons.

Rumours of a row between Ferguson and Keane at United's training camp in Portugal three weeks ago have surfaced, with subsequent speculation that it was the major reason why the United captain is missing from Ferguson's 24-man party, rather than the hamstring injury he is said to be suffering from.

Keane's adviser Michael Kennedy yesterday rejected such talk, insisting the claims were "without foundation". And Ferguson added his weight to the argument in typically blunt terms when he addressed the media prior to today's encounter with Beijing Hyundai.

"Roy Keane is injured, it is as simple as that," said Ferguson. "You can't travel if you are injured. There is nothing else to say."

Given the esteem with which he holds Keane, the suggestion Ferguson might prevent him being part of a tour which is such a vital part of United's pre-season programme always appeared a little odd.

Throughout his 12-year Old Trafford career, the influential 33-year-old midfielder has always been one of Ferguson's closes allies.

In recent times, the Scot has even adjusted United's tactics to take some of the pressure off his captain, while he has also suggested he could replace him as manager at some stage.

However, it is becoming apparent the pair did not share the same philosophy over United's trip to Portugal.

In an effort to avoid the early season stumble which wrecked last season's title challenge, Ferguson called his squad back a week earlier than usual, but with training on the Algarve restricted to half daily sessions, the United boss decided to let wives and children accompany his squad for the duration of the week-long stay.

It seems the move did not go down well with Keane, who famously stormed out of the World Cup preparations in Saipan three years ago after voicing sustained complaints over Mick McCarthy's training methods and the facilities available.

After two successive failures in the Premiership and Champions League, the notoriously single-minded midfielder felt the Old Trafford squad should have been concentrating their energies solely on training - and is thought to have told Ferguson so in a typically frank manner.

Given the combustible nature of both characters, the response is likely to have been equally forthright, but it would be a major surprise if either allowed the row to rumble on any further.

Ferguson may have ended the debate over Keane's non-appearance on the Far East tour but he is still unsure how he will eventually replace his long-serving captain.

With Steven Gerrard off limits and Michael Essien bound for Chelsea, the United boss has started to look for suitable candidates within his own squad.

And Alan Smith is proving himself to be the most likely choice.

The former Leeds striker earned Ferguson's praise for the way he anchored United's midfield in the second-half of their 2-0 win over Hong Kong on Saturday and Smith is likely to find himself occupying a similar role against Beijing Hyundai this evening.

"We keep talking about how we are going to find another Roy Keane but that is impossible," said Ferguson.

"It is pointless looking for a replacement because there simply isn't one.

"What we have to do is look within our own squad to see if there is a similar type of player who can play that role.

"Darren Fletcher, Quinton Fortune and Phil Neville can all do the job but at the moment we are experimenting with Alan Smith.

"He is enjoying it, which is the main thing, so we will see how it unfolds."