Nike blew the door wide open for Under Armour's success

Before Stephen Curry was Under Armour's biggest star, he was rejected by Nike.

Nike passed over the basketball star twice, reports Darren Rovell at ESPN.

"Two years ago, Nike had a chance to pay Curry a lot of money and lock him up for the future. After offering less than $2.5 million a year, Nike had a second chance - this time to match Under Armour's new offer," Rovell writes. "Unsure that Curry would ever be able to sell signature shoes, Nike let him go."

Curry is proving that Nike underestimated him.

The athlete's Under Armour shoe, Curry One, is "essentially sold out, save for sizes 14, 15, and 16," according to ESPN.

The Curry One is also the best-selling item on Under Armour's website.

Under Armour executives tell ESPN that Curry has a "unique blend" that appeals to customers.

"On the court, he plays basketball like it's a video game and someone young players can, and want to, emulate because of his size, handle, shot, strong work ethic and basketball IQ," an executive said. "Off the court, his humility, authenticity and leadership style are qualities that fans of all ages appreciate and respect."

The company has also scored notable endorsement deals with boxing legend Muhammad Ali and golf champion Jordan Spieth.

Under Armour is the second-largest US sportswear company behind Nike, with more than $3 billion in revenue last year.

The brand still has only a fraction of Nike's $28 billion in annual revenue.