Six Ninety One (Congrats), currently North America's winningest Thoroughbred with nine victories in 2021, won an 870-yard Quarter Horse race by a nose Tuesday at Arizona Downs. "The victory doesn't count toward the 9-year-old gelding's lead as the winningest Thoroughbred, though. Equibase separately ranks Quarter Horse races in their own category. But Six Ninety One still has a two-win cushion over four other Thoroughbreds tied with seven victories apiece. Either way, 10 total mixed-meet victories through nearly seven months of racing is a pretty noteworthy achievement. In all of 2020,...