Peter Byrne/PA Archive/Press Association ImagesLukasz Fabianski may have been Arsenals FA Cup hero, but the goalkeeper's decision to leave the Gunners has left Arsene Wenger with a void in his squad which needs filling. After seven years with the North London side, Fabianski has moved to Swansea City, a club where he should receive the first team football he desires. Although the Poland international was only used in the cup competitions by Wenger, his role within the squad should not be underestimated. He provided current number one, Wojciech Szczesny, with competition and spurred the 24-year-old on when complacency appeared to be creeping into his game. Finding a back-up goalkeeper is notoriously difficult. Very few players are happy to just sit on the bench, especially when they are in the earlier stages of their career. Consequently, clubs have been looking to sign experienced goalkeepers as their number two option. Mark Schwarzers move to Chelsea is a prime example of this. For Wenger, the same dilemma must now be dealt with. The Frenchman must bring in a goalkeeper who will challenge Szczesny, but that player must also be willing to accept that he will most likely spend the majority of the season on the bench. Unless, of course, Szczesnys form declines significantly. The World Cup is always an opportunity for goalkeepers to shine and this years tournament has been no different. Despite the plethora of goals which have been scored, shot stoppers from across the globe have been catching the eye in Brazil. For Wenger, it has provided him with the perfect opportunity to scout a new goalkeeper to compete with Szczesny and bolster his defensive options.