Born in Buenos Aires, Placente started playing professionally in 1996 with Argentinos Juniors, before moving to Argentine giant River Plate in 1997. He transferred to Bayer 04 Leverkusen in 2001, where he played until 2005 when his contract expired. Subsequently, he turned down an offer from English club Everton FC to join Celta de Vigo. While at Leverkusen he played in the 2002 UEFA Champions League Final.