Sordo was born in Carrara, Tuscany. He made his professional debuts at not yet 18 with Torino FC, remaining seven seasons with the club. In the final of the 1991–92 UEFA Cup, in the dying minutes of the second leg against AFC Ajax, after a 2–2 draw in Italy, he hit the post in an eventual 0–0 draw (and aggregate loss). In 1993, he appeared in both legs of "Toro"'s conquest of the Coppa Italia, a 5–5 aggregate win over A.S. Roma.