Spain's Nicolas Almagro rallied to defeat Argentina's Juan Monaco 4-6, 6-0, 6-3 on Friday to advance to the semifinals of the German Open in Hamburg.

The third-seeded Spaniard initially found himself on the short end of the baseline rallies, but gradually lifted his game to hand Monaco a "bagel" in the second set and wrap up the match in comfortable fashion.

Monaco got away with spinning in his first serve in the opening set, but won fewer than 50 percent of his first-serve points over the final two sets as Almagro found his groove on his ground strokes.

Next up for the Spaniard in Saturday's semifinals will be the winner of the quarterfinal contest between German No. 2 seed Tommy Haas and Italy's Fabio Fognini.

Also Friday, Argentine qualifier Federico Delbonis upset 14th-seeded Spaniard Fernando Verdasco 6-7 (5-7), 7-6 (10-8), 6-4 and will next play either top seed Roger Federer of Switzerland - a four-time winner of this event - or Germany's Florian Mayer in the semifinals.

The German Open used to be a major tune-up for the French Open but has been a lesser-tier event since 2009. EFE