Miami Marlins outfielder Giancarlo Stanton’s record-setting 13-year, $325 million contract features a backloaded pay structure that will allow the franchise the payroll flexibility to pursue free agents in the next few years, ESPN’s Jayson Stark reports. Stanton will be paid a total of just $30 million over the next three seasons and $107 million in the first six years of his contract.

The majority of Stanton’s guaranteed money kicks in after the 2020 season, when he would be 30 years old and first able to exercise the opt-out clause in his contract. If Stanton chooses to remain with the Marlins for the final seven years of the deal, he will receive the final $218 million in guaranteed money, an average of $31.14 million per season. If Stanton opts out, that portion of his contract would be voided.

In addition to his opt-out clause, Stanton has a full no-trade clause throughout the life of his contract. Stanton purposely sought the back-loaded deal in order to give the Marlins a chance to sign complimentary players and pursue a playoff berth, Stark notes. To that end, Miami has already begun pursuit of free agent first baseman Adam LaRoche, who hit 26 home runs and drove in 92 runs in 2014. The $325 million contract is the largest in the history of North American sports, surpassing the $275 million deal Alex Rodriguez signed with the New York Yankees in 2008.

The Marlins will officially announce the Stanton signing on Wednesday. Stanton was not scheduled to become a free agent until after the 2016 MLB season. He was the Marlins' highest-paid player in 2014, earning $6.5 million on a one-year deal.

The 25-year-old outfielder led the National League with 37 home runs and a .555 slugging percentage last season. He also made his second All-Star game appearance and finished second in MVP voting.