Chelsea agree £7.5m fee for Villa's Martinez

Martinez won the Europa League with Villa and reached the World Cup final with Argentina last season [Getty Images]Chelsea have agreed a £7.5m fee to sign Aston Villa goalkeeper Emiliano Martinez.The Argentina international, 33, is set to undergo a medical in London and strengthen the goalkeeping group at Stamford Bridge.It follows concerns over the performances of Robert Sanchez, particularly in the wake of Monday's 3-2 win over Fulham.Sanchez, who has been Chelsea's first-choice goalkeep