Group II stakes-placed Tumblebrutus, a full brother to prominent freshman sire Giant's Causeway, has been retired from racing and will enter stud at John T.L. Jones III and Robert Trussell's Walmac International near Lexington. His fee is $6,000 live foal.A 3-year-old son of Storm Cat, Tumblebrutus won or placed in four of seven starts in Europe and North America and earned $48,794. He ran second in the Galileo E.B.F. Futurity (Ire-II). Tumblebrutus is out of grade II winner Mariah's Storm (by Rahy). Giant's Causeway's progeny earnings are more than $1 million.