Thiago Alcântara has a "good chance" of signing for Manchester United this week for about £17m on a five-year deal, though whether David Moyes can complete the transfer of the Barcelona midfielder before the club fly out on their three-week pre-season tour on Wednesday is unlikely.

United appeared to have lost out on Thiago after Barcelona offered the Spain international assurances that he would receive regular game time. But according to a highly placed source it is understood that the chances of Thiago choosing United have been greatly enhanced, with the 22-year-old set to receive much-improved terms on his current £30,000-a-week contract.

If Thiago does decide on United he would be Moyes's first major signing since replacing Sir Alex Ferguson, and be a player who would strengthen the manager's midfield options while adding a dimension to the side's style under the Scot.

Thiago, who captained Spain's triumphant Under-21 team to the Euro 2013 championship, poses an attacking threat that has been missing from United's midfield since the now retired Paul Scholes began operating in a more reserved role. An illustration of Thiago's threat came in the hat-trick he scored in Spain's 4-2 win over Italy in the Euro 2013 final.

If Thiago does sign before Wednesday, whether he would join his new team-mates on their tour of Thailand, Australia, Japan and Hong Kong would depend on his fitness, the view of the club's medical department and Moyes's preference. New signings at United are often required to have a week of tests and training before they are available for selection. Yet even if Thiago were not to play, the manager may decide that he should fly out at some stage for team-bonding purposes.

Nemanja Vidic can expect to be offered a new one-year deal some time next season in keeping with United's policy of offering only 12-month terms to players who are in their 30s.

Vidic, the club captain, is 32 in October and his contract ends next summer. But despite talks not starting over a new deal and the two recent serious knee injuries inside a year potentially threatening his future at the club, this is usual practice at United. Last season Ryan Giggs did not sign his latest one-year deal until spring.

The prospect of the unsettled Wayne Rooney deciding to run down some or all of his contract does not concern United. Rooney has two years left of a salary worth up to £300,000 a week, and his future is unclear following last season's uneven campaign under Ferguson.

On Friday Moyes stated categorically that Rooney is not for sale but was unable to confirm if the forward is content to stay.

While Rooney's silence regarding his position may be a bargaining ploy regarding any new deal offered by United, if he decided to allow his contract to run down to only 18 months remaining, or less, this would not disconcert United, despite the decrease in his value. With Rooney turning 28 in October, he runs the risk of his prospective earnings in any new contract falling as he nears 30.