What stake was held on June 6, 2015 that the American Thoroughbred racehorse Frosted attended?
Frosted (horse):  Prior to that, despite winning several stakes races, he was best known for finishing behind American Pharoah four times, including a runner-up performance in the 2015 Belmont Stakes. 2015 Belmont Stakes: The 2015 Belmont Stakes (known as the 147th Belmont Stakes presented by DraftKings for sponsorship reasons) was the 147th in the Belmont Stakes series.
2015 Belmont Stakes