Complex sentence: At the 2014 US Open, he pull off a upset against world no.5 David Ferrer in reach the fourth round, where he was defeated by eventual champion Marin Cilic in five sets.
Split into simpler sentences: At the 2014 US Open, he pull off a upset against world no.5 David Ferrer in reach the fourth round. However, he was defeated by Marin Cilic in five sets.