Mike Greenberg jokingly weighs his chances of beating Chris Johnson's 40-yard dash combine record to secure the island Adidas is offering. (1:48)

Breaking the record for the fastest 40-yard dash at the NFL combine isn't only about bragging rights. It might be about winning an entire island.

Adidas is offering an island to any prospect who breaks the 4.24-second time clocked at the combine by Chris Johnson in 2008, as long as he does it in the company's 2017 Adizero 5-Star 40 cleats and agrees to endorse the company's shoes for the entire 2017-18 season.

Adidas is offering an island to any prospect who breaks the 4.24-second time clocked at the combine by Chris Johnson in 2008. AP Photo/Michael Conroy

The fine print says that Adidas agrees to provide a winner with an island "as soon as reasonably possible" but that the company can also just pay the athlete $1 million instead. The company is not responsible for the payment of any taxes on the prize.

A search of private-island sale sites reveals many islands in Canada and Central America that can be bought for less than $1 million.

Eric Dickerson, who owns the NFL record for single-season rushing yards, joked that the potential award is much better than what he got when he went for 2,105 yards in 1984.

That beats the carrot cake @adidasFballUS gave me for breaking the @NFL single season rushing yards record lol #NFLCombine #ED2105 https://t.co/VmPaxkrpbi — Eric Dickerson (@EricDickerson) February 28, 2017

Over the years, Adidas has given endorsement deals or cash prizes of $100,000 to the prospects who have run the fastest time. It offered $1 million cash last year if someone could set a new mark.

Times are expected to be challenged at the NFL combine in Indianapolis on Friday and Saturday when the running backs and wide receivers go through the drills.