The third-seeded Spaniard needed just 71 minutes to beat Filippo Volandri 6-2 6-2 for his 11th consecutive win in the Abierto Mexicano Telcel Open.
Thomaz Bellucci followed up his defeat of second Fernando Verdasco by beating Ivan Navarro.
Brazilian Bellucci made a nightmare start as the lost the first set 6-1, winning less than half the points on his own serve.
But he battled back to take the next two sets 6-4 6-3.
Defending champion David Ferrer is also through with a 6-2 6-2 win over home favourite Santiago Gonzalez.
Fourth seed Stanislas Wawrinka had to come from a set down to beat Italy's Fabio Fognini 5-7 6-3 7-5 while sixth seed Alexandr Dolgopolov beat Carlos Belocq 6-4 6-1. But fifth seed Albert Montanes was dumped out in straight sets by Santiago Giraldo.
Poland's Lukas Kubot advanced as he fought back from losing a tight first set tie-break to defeat Eduardo Schwank 6-7 (8/10) 6-4 6-4 in a contest stretching to almost three hours.
Argentina's Juan Monaco was another man to make it through as the seventh seed saw off Pablo Cuevas 6-3 6-4.
In the women's draw top seed Julia Goerges was edged out 6-4 7-6 (8/6) by Anabel Medina Garrigues but Argentina's Gisela Dulko continues to make serene progress after her 6-1 6-1.
Lourdes Dominguez Lino, fresh from her success in Bogota last week, followed up her win over second seed Polona Hercog with a 6-1 6-1 win over Pauline Parmentier.
Laura Pous-Tio beat Sorana Cirstea 6-2 6-1 while Lesia Tsurenko's withdrawal when trailing 6-3 1-0 saw Arantxa Parra Santonja progress.
Greta Arn defeated Renata Voracova 6-3 2-6 6-4 and Johanna Larsson recovered from a poor start to beat Mathilde Johansson 2-6 6-2 6-3.
Carla Suarez Navarro advanced with a 6-4 6-3 win over Madalina Gojnea.