Alexis Sanchez pictured at Manchester United before leaving to Italy. Photo:

Alexis Sanchez's ill-fated swap with Henrikh Mkhitaryan will end up costing Manchester United and Arsenal £46.5million in basic salary alone.

Mkhitaryan moved to Roma on loan from Arsenal on Monday, joining Sanchez in Italy less than a week after the United flop signed for Inter Milan until the end of the season.

It came just 19 months after the two stars were involved in a rare player exchange that will go down as one of the worst deals — and most expensive mistakes — in Premier League history.

United have suffered most with Sanchez’s £300,000-a-week basic wage costing them £24.9m since they gazumped rivals Manchester City to sign him in the January transfer window last year.

That does not take into account the additional £100,000-a-week he has earned in image rights and bonuses that, in theory, could have taken his weekly pay up to £560,000.

Worse still, United have been forced to heavily subsidise Sanchez’s wages at Inter to get rid of the 30-year-old winger. They will contribute £6.5m for the remaining 10 months of the season with the Italian club stumping up £4.5m.

That means Sanchez, who made just 45 appearances and scored five goals in his time at Old Trafford, will remain one of United’s higher earners even though he no longer plays for the club.

Meanwhile, Mkhitaryan’s basic £180,000-a-week salary has cost Arsenal £15.1m in wages, although the figure was closer to £200,000 with bonuses for a player who scored only nine goals in 59 games.

At least Roma have agreed to cover the entirety of the 30-year-old Armenian’s salary until the end of the season and are also paying a loan fee of between £3m and £4m.

However, neither of the deals for Sanchez and Mkhitaryan includes an obligation for Inter or Roma to buy them next summer.

Both players could return to their English clubs or go out on loan again — potentially costing United and Arsenal even more money.

Despite growing disillusioned over his lack of playing time, Sanchez insisted yesterday that he does not regret the move to Old Trafford.

‘I’m very happy I went to Manchester United,’ he said. ‘I wanted to join them and win everything. I don’t regret going there.

‘But I’ve always said to my friends: I want to play. If they would let me play, I’ll do my best. Sometimes I’d play 60 minutes then I wouldn’t play the next game, and I didn’t know why.’

Daily Mail