Sham is often regarded as one of the fastest racehorses of all time -- but unfortunately, he spent his career chasing arguably the best ever in Secretariat (shown here winning the 1973 Belmont). The two first met in preparation for the 1973 Kentucky Derby at the Wood Memorial at Aqueduct, with Sham placing and Secretariat showing. This would be the only time Sham would get the best of Secretariat, however, as he finished second in both the Kentucky Derby and Preakness while Secretariat swept the Triple Crown for the first time in a quarter-century. Their Derby showdown was one of the most remarkable ever, with Secretariat running a time of 1:59.40, the first horse to break two minutes for 1 1/4 miles. While official times for non-winners were not recorded, it is estimated by many that Sham broke two minutes as well, losing by only 2 1/2 lengths.