Under Armour's share price enjoyed a two per cent lift yesterday after sponsored golfer Jordan Spieth secured his second major of the year.
The prodigious 21-year-old, who became the youngest player to win the US Open on Sunday, is just six months into a 10-year deal that requires him to be decked out head to toe in the sportswear's golfing gear.
Shares in Under Armour closed at a price of $84.90, giving the company a market value of $17bn, slightly higher than rival Adidas' €14.9bn ($16.7bn) market cap.
Spieth is part of a swelling portfolio of sporting talent recently added to the Under Armour ranks which also includes tennis superstar Andy Murray, Superbowl winner Tom Brady, boxer Saul 'Canelo' Alvarez, Manchester United winger Memphis Depay and the NBA's MVP (most valuable player) Steph Curry.
Like its collection of often young, up-and-coming stars, Under Armour has rapidly grown in recent months, with its share price surging over 24 per cent since the start of the year (compared to Nike's 11 per cent) and is expecting to record full-year turnover of $3.78bn on last year's $3.08bn.
The popular and photogenic Spieth, snapped up by Under Armour before his breakout success this season, took home $1.8m in prize money from the US Open, to take his career earnings past $15m.
So far this year the young Texan has pocketed $7.8m after becoming the first player since Tiger Woods in 2002 to win both the Masters and the US Open in the same year.