Second-seeded Nikolay Davydenko of Russia defeated seventh-seeded Marc Gicquel of France 6-4, 5-7, 6-3. Davydenko will face unseeded Florent Serra of France, who defeated Flavio Cipolla of Italy 6-1, 6-1.
Federer stayed mostly on the baseline and was broken twice in the clay-court match. Gil completed his rain-postponed second-round match earlier in the day, defeating Joao Sousa of Portugal 7-6 (5), 6-2.
Gil "played an excellent set and a half," the top-ranked Federer said. "Thank God I could use the rain delays to improve my level of play."
Among the women, second-seeded Maria Kirilenko of Russia routed fifth-seeded Tathiana Garbin of Italy 6-0, 6-1, and Iveta Benesova of the Czech Republic upset eighth-seeded Camille Pin of France 3-6, 6-2, 6-3.
Federer squandered a break point at 2-2 in the first set, and after the next game a downpour halted play for almost 40 minutes. The Swiss then broke serve in the sixth game, but Gil responded by breaking back. Federer broke again to clinch the first set.
The players traded breaks to start the second set before another downpour suspended play. Federer then dominated the rest of the way.