Aston Villa have organised two matches against Celtic in aid of Stiliyan Petrov.The Bulgarian international's two British clubs will face one another as part of their pre-season preparations ahead of their next two campaigns. The games will be played at Villa Park and Celtic Park, preceded by matches involving former players from both clubs.It is expected that the money raised after administrative expenses will go towards Leukaemia research. Petrov also organised for Villa's first-team to contribute to a benevolent fund for the club's former players - despite just having heard the diagnosis about his illness. A source said: 'It was the action of a true captain.'