Manchester United have enquired over the availability of Southampton left-back Luke Shaw as they draw up a list of potential alternatives to Everton’s Leighton Baines.

The highly-rated Shaw 18 is regarded as one of England’s best prospects and United manager David Moyes has checked on him after facing up to the prospect of missing out on Baines.

Shaw signed a five-season contract at Southampton in the summer and starred in the opening-weekend victory over West Brom to underline his importance to the Saints who do not need to sell.

But the teenager who is rated at about £10million has come under renewed scrutiny by United in the past few days after a joint £28m bid – rising to £30m – for Baines and his club-mate Marouane Fellaini was dismissed as “derisory and insulting” by the Goodison Park club.

United are expected to increase their offer to about £35m over the coming days and are unlikely to split the bid and just go for one or the other.

Yet there seems little chance of Everton caving in even at that improved figure with chairman Bill Kenwright having made keeping Baines in particular his priority.

Everton’s trenchant stance with United is partly motivated by their anger over how Moyes was effectively appointed behind their backs by Sir Alex Ferguson when still in charge at Goodison.

Former United chief executive David Gill apologised to Everton for the way Moyes was installed as Ferguson’s successor. But resentment still lingers.

There is also the fact that Everton believed they had an agreement with Gill’s replacement Ed Woodward that United would not bid again for Baines when a second offer of £12m was rebuffed. A first bid of £9m was immediately rejected.

Everton manager Roberto Martinez added his voice to the chorus of condemnation at the club towards United by dismissing the offer – which was made just 48 hours before the season opener with Norwich – as a “waste of time”.

He said: “It has been well documented what happened with the transfer speculation.