Manchester United are in a frantic final push to recoup as much money as possible before the transfer window closes following Ángel di María’s £59.7m arrival by offloading a string of high-earning fringe players, with this driving the decision to allow Danny Welbeck, who could cost up to £20m and earns at least £80,000 a week, to depart.

United’s determination to add fresh acquisitions before 1 September is also behind the club’s intention to sell. Targets considered by Louis van Gaal include Sporting Lisbon’s William Carvalho, who would cost £24m, Juventus’s Arturo Vidal, worth at least £30m, Milan’s Nigel de Jong, valued at £10m, and Ajax’s Daley Blind, who would be at least £18m.

United’s status as one of the world’s best paying clubs has caused them difficulty all summer to unload players, with the Guardian having learned that salaries are far higher that previously thought.

This was illustrated by the loan-deal that took Nani, who earns £115,000 a week, to Sporting Lisbon as part of the £16m transfer of Marcos Rojo from the Portuguese club. United agreed to pay the winger’s salary while there, which equates to around £4.14m for the season.

Nani heads a list of players who draw lucrative salaries despite being deemed by Van Gaal as being surplus to requirements. Ashley Young, who the club would listen to serious offers for, earns £115,000 a week, which equates to an £11.9m salary over the final two years of his deal.

Javier Hernández, the subject of a bidding war between Valencia and Juventus, has two years remaining on a basic salary of up to £88,000, a total of £9.15m.

Anderson, now back at United following last season’s loan at Fiorentina, earns £80,000 a-week, which is £4.16m until his deal ends next summer. Shinji Kagawa, who is interesting his former club Borussia Dortmund, is paid £70,000 a week as is Marouane Fellaini, though the latter’s ankle injury means United will not be able to sell him this window. As both players have two seasons left on their terms, the club is due to pay them £7.2m each.

Tom Cleverley, a target for Aston Villa, is one of United’s lowest earners, drawing a basic wage of only £30,000 per week, though his deal is heavily incentivised so can be markedly higher. As Cleverley’s contract expires in May, any terms Villa offer would have to be attractive or he could choose to wait and leave then as a free agent.

If United were to sell Welbeck, Young, Hernández, Anderson, Kagawa and Cleverley before the end of the transfer window, they would save a total of £463,000 a week. With the potential departures of Nani and Fellaini in the future, this figure could reach a staggering £646,000 a week that the club would save.

Welbeck was told by Van Gaal that he could stay at United but would have to accept not being a first-choice striker as Wayne Rooney and Robin van Persie enjoy this status. With the 23-year-old having been frustrated at a lack of opportunity at centre-forward since last season under David Moyes, Welbeck has been effectively given little choice but to leave.

The club have stipulated that he cannot join a top six club though if Tottenham Hotspur who are understood to be interested in taking the striker, possibly on loan, were to offer the right deal this would test United’s resolve.

Ray Wilkins has questioned the figure United paid for Di María, and feels the money may have been better spent elsewhere. “They are putting the roof on before the foundations of the house,” Wilkins told TalkSport. “I think they spent the £60m unwisely on Di Maria. Why don’t they go and pay £35m for Hummels first? We know Dortmund, as good a side as they are, are a selling club. Take him out of Dortmund and put him in alongside Phil Jones. Then go and get Khedira for £25m. There’s your £60m and you already look more solid.”

While Di María is available for Saturday’s trip to Burnley, but his compatriot Rojo is yet to receive his.

Van Gaal said: “Rojo is working on his [work] permit because he has to go abroad for that. The difference between Ángel di María and Rojo is that he has an Italian passport and Rojo does not. He has an Argentinian passport and he has to work for it. Now he is abroad in Madrid to work at the embassy, but it takes more time than we expected.”