Question: What is the birth date of this Spanish footballer, who was added as a holding midfielder in the 2012-13 FC Bayern Munich season?
Sentence (from "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.
Relevant evidence: Yes