Guillermo Ignacio Cañas (born November 25, 1977), often referred to as Willy Cañas, is a retired Argentine professional tennis player. He was born in Argentina's capital, Buenos Aires, and named after Argentine tennis star Guillermo Vilas. His career-high singles ranking was World No. 8, achieved in June 2005. Cañas was the coach of Ernests Gulbis from July 2011 until May 2012.