This year marks the 50th anniversary of Canonero II posting arguably the most improbable upset in Derby history. Canonero quickly became the darling of Venezuela, where the colt had trained prior to making an arduous journey to the U.S. to win the 1971 Derby as a member of the mutuel field. The $1,200 yearling purchase went on to win the Preakness but faded to fourth in the Belmont Stakes. Carrying saddletowel No. 15 and jockey Gustavo Avila, Canonero rallied to win the Derby by 3 3/4 lengths over Jim French. It’s a story that’s been regaled for years as the ultimate underdog tale and one that Derby fans have come to embrace as all-time favorite. ◗ Lone Rock earned a 94 Beyer Speed Figure with a 3 3/4-length victory in the $128,000 Opening Verse going 1 1/2 miles on a fast main track Tuesday. Ramon Vazquez was in for the mount for Flying P Stable and trainer Robertino Diodoro. Lone Rock paid $3.80.