WINSTON-SALEM, N.C. -- The biggest news at a soggy Winston-Salem Open on Monday wasn't made by who advanced. It was who pulled out.
Two-time defending champion John Isner and top seed Tomas Berdych withdrew from the tournament.
After the start of the day was delayed 4 hours, 10 minutes due to rain, two seeded players were upset in the second round Monday night.
Pablo Andujar, the No. 16 seed, was beaten by Yen-Hsun Lu of Taiwan 6-4, 6-3, and 12th-seeded Lukas Rosol was upset by Robin Haase of the Netherlands 6-4, 3-6, 7-5.
Sixth-seeded American Sam Querrey was the only seeded player to advance, beating Guillermo Garcia-Lopez of Spain 4-6, 6-3, 6-4.
Eleven seeded players -- including No. 2 seed Andreas Seppi -- play their second-round matches Tuesday.
The day's big story was the withdrawals of the two players who met in last year's final: Isner pulled out with a hip injury, and Berdych withdrew with right shoulder pain. Isner beat Berdych in last year's championship match.
Both players said they wanted to be healthy for the U.S. Open, which begins next week.
That leaves the tournament without its two highest-ranked players, and perhaps its biggest draws.
Isner, a Greensboro native, considers this his hometown tournament and called it "one of my favorite tournaments of the year." He won this event in each of its first two years of existence.
He withdrew one day after falling to Rafael Nadal in the Western & Southern Open final in Cincinnati. Injuries kept him from playing two other majors -- the Australian Open and Wimbledon.
Berdych moved up one spot to fifth in the ATP rankings released Monday. Isner jumped eight spots to No. 14.
The highest-ranked player remaining in the field is fourth-seeded Tommy Robredo of Spain at No. 22.
Eleven first-round matches were played earlier Monday: James Blake beat fellow American Rhyne Williams 6-1, 7-5; Qualifier Steve Johnson beat fellow American Bobby Reynolds 6-1, 6-2; and German David Goffin advanced when American Jack Sock withdrew in the third set with Goffin leading 4-6, 6-3, 1-0.
Roberto Bautista Agut of Spain defeated Danish qualifier Frederik Nielsen 6-1, 6-3; Qualifier Thiemo de Bakker beat Igor Sijsling 3-6, 6-4, 6-4 in a matchup of players from the Netherlands; and Nicolas Mahut of France topped Poland's Lukasz Kubot 6-3, 6-1.
Ricardas Berankis of Lithuania beat Kenny de Schepper 7-6 (3), 6-4. Spain's Daniel Gimeno-Traver edged Frenchman Edouard Roger-Vasselin 7-6 (6), 7-6 (5). Guido Pella of Argentina defeated countryman Leonardo Mayer 7-6 (5), 7-6 (4). Guillaume Rufin of France eliminated Uzbekistan's Denis Istomin 6-4, 3-6, 6-3. And American Tim Smyczek beat Michael Russell of the U.S. 6-4, 6-7 (6), 6-4.