World Cup 2014: Get to Know Portugal's Cristiano Ronaldo

— -- Despite struggling with an injury at the 2014 FIFA World Cup, Cristiano Ronaldo is still the player to watch as the United States plays Portugal in Manaus, Brazil, later today.

The 29-year-old winger won his second FIFA Player of the Year award this season, beating out Argentine rival Lionel Messi. He also won the UEFA Champion's League with Real Madrid, scoring in the final, just last month.

Ronaldo is Portugal's all-time leading scorer, having found the net 49 times in 112 appearances. But he didn't see much of the ball in Germany's 4-0 shellacking of Portugal last week.

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The biggest knock against Ronaldo? He falls down rather easily sometimes and hasn't always performed well in major tournaments, having only scored twice in two previous World Cups. But his 17 goals in the UEFA Champion's League this past season set a new record, so the theory of him under-performing on the biggest stages may have gone out the window.

Ronaldo's fame also extends beyond the pitch. He and model girlfriend Irina Shayk were recently featured on the cover of Vogue magazine in Spain.

He also has his own line of underwear, the CR7 Collection. With more than 26 million Twitter followers and 82 million Facebook fans, sports marketing research firm Repucom just named him the most marketable soccer player in the world.

Whether you swoon over his play or his good looks, Ronaldo will be one to watch this summer.

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