Bryce Harper was offered a 10-year, $300 million contract offer from the Washington Nationals with no opt-out clauses, according to Chelsea Janes of the Washington Post.

But Harper reportedly turned down the contract offer, with Ken Rosenthal of The Athletic adding that the Nationals "surely knew" the 2015 National League MVP wouldn't accept the mammoth deal.

And with that, the winner of the Bryce Harper sweepstakes will have to be willing to go above $300 million. New York Yankees slugger Giancarlo Stanton landed the biggest contract in MLB history from the Miami Marlins in 2014 - a mega 13-year deal worth $325 million.

Harper is a six-time All-Star and widely considered the co-face of baseball, alongside Mike Trout. However, the 26-year-old had a down season, batting a mere .249 with 34 home  runs and 100 RBI. Harper posted an OPS of .889 - slightly below his career total of .900.

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Credit: Geoff Burke-USA TODAY Sports

The Nationals, Philadelphia Phillies, New York Yankees and Chicago Cubs have all been mentioned as possible suitors in the Harper sweepstakes. Harper is close friends with Cubs star Kris Bryant, and he'd certainly have the chance to chase championship rings with a team that is two years removed from a World Series.

But the Phillies have been widely considered a favorite to land both Harper and fellow prized free agent Manny Machado. Jon Heyman of Fancred Sports recently outlined that with plenty of money to spend (thanks to their TV contracts), the Phillies could be a major player in the winter market.

With Harper only being 26 years of age, there's good reason to believe that he'll surpass Stanton's contract a the largest in MLB history. Harper may have had a down year, but he's been one of the game's top all-around players since breaking into the majors six years ago.

Now, we just wait and see which team will pony up the money for the All-Star slugger.

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