Getty Images SportMitchell FrettonArsenal star William Saliba explains what he thinks he's missing to become 'the best defender in the world'W. SalibaArsenalPremier LeagueArsenal star William Saliba says he cannot be considered the best defender in the world until he wins silverware.Article continues belowArticle continues belowArticle continues belowArticle continues belowSaliba established as a top defender in EuropePart of best defence in Premier League with ArsenalBelieves he must win trophies to be at the top