SARATOGA SPRINGS — It might be the greatest horse-betting system ever.

For the 11th time since 1994, Hall of Fame trainer Bill Mott, who turned 58 on Friday, saddled a winner at the Old Spa on his birthday.

This time, the reward for following up on that simple fact was huge: A $26.20 win payoff on Juddmonte Farm’s Reach a Decision in the second race, for maidens going 1 3/16ths mile on turf. It was the first time the 3-year-old colt raced on grass, which is Mott’s specialty.

Reach a Decision pressed the pace under a snug hold by Eddie Castro, inherited the lead down the backside, opened up around the far turn, then held off the rally of Colossal Gift to win by a length.

The exacta with Colossal Gift, who was the heavy favorite, returned $96.50.