An American footballer has missed out on winning himself an island - because he was wearing the wrong trainers.

Adidas said they would give away a whole island to a footballer who could break the record for the 40-yard dash.

And John Ross, a former college footballer, did just that in the NFL Combine, an event where young players showcase their abilities to coaches.

But the player had to be wearing Adidas shoes to be eligible to win - and Ross was wearing Nikes.

Adidas said they would provide an island "selected by Adidas", but it's not known which island that would be.

All that's known is that it would be worth $1m (£820,000), and the sportswear company could, if they wanted, give $1m as a prize instead.

John Ross ran 40 yards in 4.22 seconds, beating the previous record of 4.24 seconds set in 2008.

"I really can't swim that well," Ross told ESPN. "And I don't have a boat, so, you know, I had to run in Nikes."

But John clearly failed to read the T&Cs.

Wearing Adidas shoes was the first clause in their terms and conditions for winning the island - and athletes would also have had to enter into an endorsement deal with Adidas before next season.

Ross signed a deal with Nike shortly after he ran the record time, according to ESPN.

He beat the nine-year record set by Chris Johnson, who is now a running back for the Arizona Cardinals.

After he set the record in 2008, Johnson went on to be picked in the first round of the draft by the Tennessee Titans.

It's not every day you miss out on winning your own island. John seems to be handling it ok though.

That sponsorship deal with Nike is probably softening the blow.

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