Harper's is not only larger than the 10-year, $300 million contract infielder Manny Machado signed with the San Diego Padres earlier this month - which was the largest free agent deal ever signed - but it also eclipses New York Yankees slugger Giancarlo Stanton' 13-year, $325 million contract extension that he signed as a member of the Marlins in 2017.
USA Today's Bob Nightengale and NBC Sports' Alex Pavlovic shed some light on the Giants' reported offer and why a deal in the Bay Area didn't work out.
Harper's deal includes a no-trade clause, no opt-outs, and no deferred money.
Ultimately, Harper chose to put down roots in Philadelphia. "Bryce wanted one city for the rest of his career".More news: Lena Dunham defends Jordyn Woods amid cheating scandal
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The extraordinary length of the contract - which runs through the 2031 season - gives the Phillies a bit of relief in terms of the average annual value ($25.38 million).
Even former players are excited about the deal. Rockies third baseman Nolan Arenado, who would have been eligible for free agency next offseason, signed a $260 million, eight-year agreement this week.
His best year was 2015, when at age 22 he hit.330 with 42 homers, 99 RBIs, 118 runs and 124 walks, amassing an OPS of 1.109.
After only 130 minor league games, Harper burst on the major league stage in 2012 and won the Rookie of the Year Award.
The 26-year-old outfielder spent his entire career with the Washington Nationals, after they selected him with the first overall pick in the 2010 MLB Draft. He had turned down the team's $17.9 million qualifying offer.
Philadelphia has been among the most active teams this offseason, adding outfielder Andrew McCutchen for $50 million over three years and reliever David Robertson for $23 million over two years, and acquiring catcher J.T. Realmuto and shortstop Jean Segura. They had a top-six payroll in each of the previous four years.