When was the German professional footballer who was a client to Roman Grill born? 
Roman Grill:  His clients include Owen Hargreaves, Philipp Lahm and Piotr Trochowski. Piotr Trochowski: Piotr Artur Trochowski (] , ] ; born 22 March 1984) is a German professional footballer who plays as an attacking midfielder and is currently unattached to a club.
22 March 1984