Citi Open preview: Isner, Monfils, Wozniacki headliners

Main draw matches on the hard courts at the FitzGerald Tennis Center in Rock Creek Park begin Monday with the championships for the men's (ATP) and women's (WTA) tours set for July 24. Isner, the top ranked American on tour, is a perennial contender in Washington, but is still looking for his first title. 3 - As in the number of Citi Open titles won by Juan Martin del Potro.