What is the birth date of this Spanish footballer, who was added as a holding midfielder in the 2012-13 FC Bayern Munich season?
2012–13 FC Bayern Munich season:  Bayern also added holding midfielder Javi Martínez after the first week of the Bundesliga season at the transfer deadline. Javi Martínez: Javier "Javi" Martínez Aginaga (] ; born 2 September 1988) is a Spanish footballer who plays for German club FC Bayern Munich as a defensive midfielder or a central defender.
i don't know