UFC 121 is slated for October 23 from the Honda Center in Anaheim, California. Headlining the event will be a heavyweight title fight between Brock Lesnar and Shane Carwin.
News of the bout between Sanchez and Thiago was first reported by PennyJoMMA.com.
Both men are looking to rebound from recent defeats, as Sanchez is coming off of consecutive defeats at the hands of B.J. Penn at lightweight and John Hathaway in his return to welterweight, and Thiago most recently suffered a setback in the form of a unanimous decision loss to Martin Kampmann at UFC 115.