Winston-Salem, NC (Sports Network) - Top seed and last year's runner-up Tomas Berdych and two-time defending champion John Isner both pulled out of the Winston-Salem Open on Monday.
The former Wimbledon runner-up Berdych cited right shoulder pain, while the third-seeded Isner exited with a hip injury. Isner ousted Berdych in last year's finale at Wake Forest University.
The 6-foot-9 North Carolina native Isner hails from nearby Greensboro.
Isner was a runner-up against former world No. 1 star Rafael Nadal at the ATP Masters 1000 event in Cincinnati on Sunday. The surging American recently titled in Atlanta and was also a hardcourt runner-up in Washington, D.C., earlier this month.
Play commenced Monday only after a four-hour rain delay, and sixth-seeded American Sam Querrey moved into round three with a victory over Spaniard Guillermo Garcia-Lopez, 4-6, 6-3, 6-4.
In two other second-round encounters, Dutchman Robin Haase upset No. 12 seed Lukas Rosol of the Czech Republic, 6-4, 3-6, 7-5; and Yen-Hsun Lu defeated 16th seed Pablo Andujar, 6-4, 6-3.
James Blake defeated Rhyne Williams, 6-1, 7-5; and Tim Smyczek downed Michael Russell, 6-4, 6-7 (6-8), 6-4. Another all-American affair saw two-time NCAA champion Steve Johnson whip journeyman Bobby Reynolds, 6-1, 6-2.
Belgian David Goffin was leading Jack Sock 4-6, 6-3, 1-0 when the American retired on Day 2. Lithuanian Ricardas Berankis, Spain's Roberto Bautista and Daniel Gimeno-Traver, Dutchman Thiemo de Bakker, Argentine Guido Pella, and France's Guillaume Rufin and Nicolas Mahut also won their first-round matches.
Winston-Salem serves as a final tune-up for the U.S. Open.