Under Armour is beginning to steal Nike and Adidas’s thunder

The company's founder Kevin Plank is a former athlete

Under Armour have taken competitors by surprise in the market and now have some of the top stars in each sport representing them Pic: Getty

Dublin Gaelic footballer Rory O’Carroll wasn’t necessarily an obvious choice when Under Armour was looking for Irish athletes to endorse. Five years ago, the company was still a challenger brand to the likes of Nike and Adidas in the US and was a relative unknown in Europe.

O’Carroll wasn’t a marquee name at the time, but he was seen as a good fit with the brand’s values. The partnership paid off. O’Carroll has ...