The four underdogs who have won Grand Slams in the last decade

#2 Marin Cilic - 2014 US Open

Marin Cilic with the US Open title in 2014

When Marin Cilic was found to have failed a drug test and was banned for four months from the game, his tennis future was left hanging in the balance. However, under such a make or break siituation, Cilic came back better than ever.

The Croat hired the only Grand Slam winner from his country – Goran Ivanisevic – as his coach, and returned to the tour at Brisbane in February 2014 where he would be beaten in the quarterfinals, ominously by Kei Nishikori. Cilic would go on to capture titles at Zagreb and Delray beach and was seeded 16^th at the US Open.

At the tournament, he beat Gilles Simon for the first time in five attempts and then defeated Roger Federer in straight sets (first victory in six attempts) to reach a maiden Grand Slam final. There he would meet his old foe Nishikori, who would also be dismantled in straight sets. The victory was the 300^th of his professional career.

Cilic would rise to a career high number 8 in the world rankings and would give a strong performance in the succeeding US Open as well, reaching the semifinals.