Fernando Tatís Jr. was 18 years old, just a low-level prospect from the Dominican Republictrying to work his way up in the San Diego Padres farm system, when he made a financialdeal that would impact his entire baseball career. And it wasn't with the Padres. Tatís signed a contract with Big League Advance, an unusual investment fund that paysminor-league players money up front in exchange for a share of their future MLBearnings. Tatís, now 22 and widely viewed as one of the sport's best young stars, today knows whatthose earnings will be. He agreed to a record-setting 14-year contract with the Padres onWednesday night worth an eye-popping $340 million, the third-highest total in MLBhistory. His new contract also creates a significant obligation for Tatís: to pay a sizable chunk ofhis new bounty—perhaps close to $30 million—to Big League Advance.