Colombia's Santiago Giraldo denied Nicolas Almagro a second straight berth in the final of the Barcelona Open BancSabadell, upsetting the Spaniard 7-5, 6-3 on Saturday.

The 26-year-old world No. 65 will square off in the final against Japanese world No. 17 Kei Nishikori, a 6-2, 6-4 winner over Latvia's Ernests Gulbis in the day's first semifinal.

The 20th-ranked Almagro pulled off the biggest surprise of the tournament by defeating countryman Rafael Nadal 2-6, 7-6 (7-5), 6-4 in Friday's quarterfinals, but he suffered a letdown after the biggest win of his career.

The Spaniard, who had never lost to Giraldo in five previous matches, seemed to feel the pressure of going from underdog to favorite in the span of 24 hours and was unable to generate the same spin and penetration he had against the world No. 1.

Giraldo squandered two chances to break Almagro's serve in the early going but he took advantage of another opportunity in the 12th game to snag the first set.

The Colombian won his quarterfinal match Friday when Germany's Philipp Kohlschreiber retired with an injury in the second set and was fresher physically and mentally on Saturday than Almagro, who needed nearly three hours to end Nadal's 41-match winning streak at the Barcelona Open.

Giraldo used that advantage to grab a service-break lead late in the second set and serve out the match at his first opportunity, although not without having to save a break point.

Almagro reached the final of this event last year, losing to Nadal in straight sets.

Sunday's final will be the first at this tournament without a Spanish player since 1996.

The Barcelona Open BancSabadell is one of the bigger tune-up events for tennis' premier clay-court tournament, the French Open, which gets underway on May 25. EFE