Lees Racing announced the sad loss on Wednesday.
“It’s with a heavy heart we announce the loss of Smart Melody today to a colic-related illness,” Lees Racing said on Twitter.
“Our thoughts are with all the staff @GooreePark and @Leesracing.”
The Gooree Stud-owned three-year-old won her first five starts, winning her first two races by a combined margin of 10.5L.
She won the Group Two Thousand Guineas Prelude during the spring before experiencing her first defeat when finishing midfield in the Thousand Guineas.
— Lees Racing (@Leesracing) December 5, 2018