Updated

Second-seeded Frenchman Gilles Simon and third-seeded American Sam Querrey posted second-round wins, while towering American John Isner went by way of the upset Wednesday at the $530,000 Nice Open, a final clay-court French Open tune-up.

Simon subdued qualifier and fellow Frenchman Guillaume Rufin 6-4, 6-3 following a lengthy mid-match rain delay, while Querrey handled Ukrainian qualifier Sergiy Stakhovsky 7-5, 6-3 and the 6-foot-9 fourth-seeded Isner gave way to Dutchman Robin Haase 6-4, 1-6, 7-5 at the Nice Lawn Tennis Club.

Simon's quarterfinal opponent on Thursday will be Spaniard Pablo Andujar, while Querrey will take on Frenchman Edouard Roger-Vasselin.

Another seeded player was dispatched during Wednesday's action, with French wild-card Gael Monfils knocking off sixth-seeded Italian Fabio Fognini by a 6-2, 7-6 (7-5) score.

Also in the round of 16, Andujar whipped Taiwan's Yen-Hsun Lu, 6-2, 6-0; the wild card Roger-Vasselin overcame Lithuanian Ricardas Berankis 2-6, 6-4, 6-2; Spain's Albert Montanes topped Romanian Victor Hanescu 7-5, 7-6 (7-2); and France's Paul-Henri Mathieu got past Argentine Carlos Berlocq 7-5, 3-6, 6-3 on Day 4. Hanescu was the Nice runner-up two years ago.

The 2013 Nice champion will earn $95,000.