By Arsenal correspondent Tony Hughes

Arsenal beat off competition from a string of top clubs headed by Liverpool to clinch the signing of Alexis Sanchez last summer in the club’s second most expensive-ever transfer.

Football Insider sources have learned that a deal was in place for Sanchez to make the £32.5million move from Barcelona to Arsenal nearly two months before he was unveiled at Emirates Stadium in mid-July.

Arsene Wenger was being diplomatic when he claimed this week that he “did not know” why Sanchez chose the Gunners ahead of Liverpool, as the two clubs prepare for Saturday lunchtime’s eagerly anticipated Premier League showdown.

Arsenal had been made aware of Sanchez’s availability long before the end of last season, and with Wenger keen to recruit a top-class forward, set their sights on clinching an early deal.

It is understood the Premier League club reached an agreement in principle during negotiations with Barcelona and the Sanchez’s representatives last May.

Chief executive Ivan Gazidis and contract negotiator Richard Law returned from talks in Madrid with the Catalan club that month having settled on the terms of a £32.5m transfer, as well as receiving an agreement from Sanchez that he would make the move to Emirates Stadium after his involvement with Chile at the World Cup.

The transfer was not formalised until the second week of July as Barcelona waited for their signing of Luis Suarez from Liverpool to be rubberstamped before officially sanctioning Sanchez’s departure.

Nevertheless, there was confidence among senior Arsenal officials that Sanchez’s head would not be turned by the interest from Liverpool, Manchester United and Juventus in the wake of his excellent performances at the World Cup.

The Merseysiders made an offer for the Chilean during the Barcelona-Suarez negotiations but Sanchez had already made his mind up to move to London and Arsenal.