Complex sentence: Born in Granollers, Barcelona, Catalonia, Valiente started his career at FC Barcelona aged 10, being club captain for most of its youth sides and playing alongside Lionel Messi, Cesc Fàbregas, Gerard Piqué and Víctor Vázquez.
Split into simpler sentences: Born in Granollers, Barcelona, Catalonia, Valiente started his career at FC Barcelona aged 10. He was a club captain for most of its youth sides, playing alongside Lionel Messi, Cesc Fàbregas, Gerard Piqué, and Víctor Vázquez.