Sao Paulo, Feb 16 (IANS): Spanish tennis star Rafael Nadal recovered from a set down to reach the semi-finals of the Brazil Open with a 3-6, 6-4, 6-4 victory over Argentina's Carlos Berlocq.

The 26-year-old will face world No. 111 Martin Alund for a place in the final after the Argentinian defeated 88th-ranked Italian Filippo Volandri 7-5, 7-6 (5), reports Xinhua.

The ATP 250 clay-court event is Nadal's second tournament since returning from a seven-month layoff with a knee injury.

"I knew there was a chance I was going to lose it, but luckily I was able to recover in the end," Nadal said after Friday's win. "I'm very happy because it was a very difficult match against a great opponent. I'm happy to reach the semi-finals and now we'll see how it goes."

Nadal admitted he had barely heard of 27-year-old Alund before the tournament.

"I know very little about him but he has been having a spectacular tournament," Nadal said. "He has been playing very well and is coming into the match with a lot of confidence."

Former world No. 3 David Nalbandian will meet Italy's Simone Bolelli in the other semifinal after the Argentinian overcame second-seed Nicolas Almagro 7-6 (5), 3-6, 7-6 (3).

Bolelli advanced to his first ATP semi-finals since 2008 by defeating Spain's Albert Montanes 6-4, 6-4.