SARATOGA SPRINGS, N.Y. - Last year, the best 2-year-old in the country belonged to owner Mike Repole and trainer Todd Pletcher. Through Sunday, the best 2-year-old in the country this year belongs to owner Mike Repole and trainer Todd Pletcher. While neither is willing to put Overdriven in the same category as Uncle Mo - last year’s 2-year-old champion - both Repole and Pletcher were all smiles Sunday after Overdriven drew clear to a four-length victory in the Grade 2, $150,000 Sanford Stakes before 18,791 at Saratoga.  Power World, second in the Grade 3 Bashford Manor at Churchill Downs last month, finished second in the Sanford, three lengths clear of Futurity Stakes winner Jack’s in the Deck. Black Rhino, Moonrush, and Tarpy’s Goal completed the order of finish. Maan was an early scratch while Bless the Soldier flipped in the gate, suffering several cuts that were enough to warrant a scratch.  Uncle Mo, last year’s 2-year-old champion, did not debut until Aug. 28 when he won by 14 1/2 lengths on Travers Day here. Overdriven, a son of Tale of the Cat, debuted on July 1, winning by 3 1/2 lengths and earning a Beyer Speed Figure of 100.  In order to make the Grade 1 Hopeful here on Sept. 5, Pletcher felt he had to run Overdriven back in relatively short period of time - 23 days - to have sufficient spacing to that race. The short turnaround was no problem for Overdriven, who, under jockey John Velazquez, stalked Black Rhino through a quarter in 22.40 seconds, engaged that rival at the three-eighths pole, and then ran away from him in the stretch.  Overdriven covered six furlongs in 1:10.60 and returned $2.60 as the 1-4 favorite. With $284,191 wagered on him to show out of $239,780, there was a minus-show pool of $45,550.  John Velazquez commented that Overdriven started to loaf a bit when he made the lead, but Velazquez simply waved the whip at him to get him to the wire first. “Once he had a target next to him he was very good,’’ Velazquez said. “He was very confident around the turn. As soon as I got passed the other horse he went to wait - he was all by himself on the lead. I didn’t want to hit him, he was running good enough, just keep him busy.’’  Overdriven covered six furlongs in 1:10.60 and returned $2.60 as the 1-4 favorite. With $284,191 wagered on him to show out of $239,780, there was a minus-show pool of $45,550.  Naturally, both Repole and Pletcher were asked to compare Overdrive to Uncle Mo.  “They both have the same owner and the same trainer,’’ Repole said. “There’s only one Uncle Mo and there’s only one Overdriven.’’  Added Pletcher: “Uncle Mo at this time a year ago was a maiden, he was a month away from debuting, but we knew he was a petty special colt. This horse is 2 for 2 now, he’s obviously a very mature 2-year-old physically and mentally, precocious, gifted with some natural talent. Nice to be in this position.’’  The victory gave Pletcher his fifth victory in the Sanford, all in the 13 runnings since 1999. He also won it with More Than Ready (1999), Chapel Royal (2003), Scat Daddy (2006), and Ready’s Image (2007). By comparison, Pletcher’s former boss, D. Wayne Lukas, won five Sanfords over 14 runnings from 1985-1998.  For Velazquez, it was his sixth victory in the Sanford. He won all five for Pletcher as well as on Buster’s Daydream in 2001.