Ernest James "Ernie" Watts (born October 23, 1945) is an American jazz and rhythm and blues musician. He plays saxophone (tenor, alto and soprano) and flute. He might be best known for his work with Charlie Haden's Quartet West and his Grammy Awards as an instrumentalist. He has also toured with The Rolling Stones, joining them on their 1981 tour and also appearing with them in the 1982 film Let's Spend the Night Together. He is noted for playing "The Mystery Horn" (actually a Conn straight-necked C Melody Saxophone) solo on Frank Zappa's album The Grand Wazoo in 1972.