Endurance, the 3-year-old trotting colt who was outstanding at two and has continued on at three to be one of the favorites for the Hambletonian, was again impressive at Pocono Downs at Mohegan Pennsylvania on Saturday afternoon, when he won his $50,502 division of the second prelim of his group's Pennsylvania Sire Stake. Endurance, who gave sire Captain Corey a Sire Stakes credit, in addition to the two he earned in Stallion Series competition Saturday, went his mile in 1:51 4/5, equaling the fastest trotting time of the year at Pocono.