MASON, Ohio -- French Open champion Juan Carlos Ferrero and Wimbledon champion Roger Federer both lost in the second round of the Tennis Masters Series-Cincinnati on Wednesday.

Ferrero was upset by unseeded Gaston Gaudio 6-7 (3), 7-6 (5), 6-4, while David Nalbandian stunned Federer 7-6 (4), 7-6 (5).

The second-seeded Ferrero had 16 aces to Gaudio's six, but was undone by 40 unforced errors and 10 double-faults at the hard-court tuneup for the U.S. Open.

Also Wednesday, Guillermo Coria, the top seed remaining at No. 6, advanced when two-time major champion Yevgeny Kafelnikov quit with a sprained ankle in the second set. No. 7 seed Andy Roddick had little trouble against Ivan Ljubicic winning 6-1, 6-4.

In other matches, James Blake eliminated Sjeng Schalken 6-1, 6-4, Flavio Saretta defeated Fabrice Santoro 7-5, 6-3, Todd Martin beat Feliciano Lopez 7-6 (3), 6-4, Robby Ginepri topped Noam Okun 7-6 (5), 6-4, Hicham Arazi beat Paul-Henri Mathieu 6-2, 6-1, and Max Mirnyi defeated Thomas Enqvist 7-6 (2), 6-4.

Information from The Associated Press was used in this report.