The Men's 2013 US Open Series was won by which Spanish player, currently World #1?
2013 US Open Series:  Rafael Nadal and Serena Williams were the US Open Series winners, making them eligible for a $1 million bonus if either also won the US Open, a feat which they both accomplished, hence receiving the largest paychecks to date for a single tennis tournament, totalling $3.6 million each. Rafael Nadal: Rafael "Rafa" Nadal Parera (] , ] ; born 3 June 1986) is a Spanish professional tennis player, currently ranked World No. 1 in men's singles.
Rafael "Rafa" Nadal Parera