Convincing win for Nadal

Rafael Nadal continued his comeback from a back injury by crushing Albert Montanes 6-1 6-2 to reach the last eight of the Rio Open.

The top seed, playing in his first tournament since losing to Stanislas Wawrinka in the Australian Open final, broke three times in each set, dropping his serve once in the second, as he made short work of his compatriot.

However despite cruising to victory in just 74 minutes, Nadal admitted his back was still troubling him.

"When you get injured in the final of a Grand Slam and stop for 2 1/2 weeks, it is not easy to come back," Nadal said.

"The back is still bothering me a little bit but I am happy with my decision to be here."

Nadal will now face Joao Sousa, with the world No 48 having beaten two Spaniards en route to the last eight.

Sousa, who shocked sixth seed Marcel Granollers in the first round, overcame Albert Ramos 7-6 (8-6) 2-6 6-3.

Fabio Fognini, the third seed from Italy, survived a second-set scare as he recorded a 7-6 (7-1) 4-6 6-3 win over Argentinian Pablo Cuevas.

Next up for Fognini is Ukraine's Alexandr Dolgopolov, who came from a set down to defeat Uruguayan qualifier Facundo Bagnis 6-7 (4-7) 6-2 7-6 (7-4).

In the women's draw fifth seed Kurumi Nara swept past Anna-Lena Friedsam 6-0 7-6 (7/3).

Lourdes Dominguez Lino came from a set down to knock out Chanelle Scheepers 2-6 7-6 (9/7) 6-1, while Teliana Pereira and qualifier Irina-Camelia Begu were other second-round winners.