MIAMI (AP) -- Giancarlo Stanton has signed his record $325 million, 13-year contract with the Miami Marlins at a news conference formally announcing the deal.

Stanton signed the deal at the start of the news conference Wednesday while sitting next to owner Jeffrey Loria. The attendance-challenged franchise drew nearly 100 members of the media for the occasion.

Miami Marlins' Giancarlo Stanton celebrates a home run against the Los Angeles Angels Aug. 25. (AP Photo/Chris Carlson, File)

The contract is the most lucrative ever for an American athlete and the longest in baseball history. It includes a no-trade clause, and Stanton can opt out after six years and $107 million.

The Marlins hadn't held a celebratory news conference on such a scale since their last spending spree, just before their ballpark opened in 2012. They went 69-93, leading to a payroll purge.

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