Buenos Aires, Argentina (SportsNetwork.com) - In a battle of former champions, Nicolas Almagro knocked out second-seeded fellow Spaniard Tommy Robredo to reach the semifinals at the Argentina Open clay court tennis tournament.

The unseeded Almagro cruised past his fellow former top-10 star Robredo in easy 6-3, 6-2 fashion at the famed Buenos Aires Lawn Tennis Club

Almagro won this event in 2011 and was the runner-up in 2012. Robredo captured the Buenos Aires title back in 2009.

Meanwhile, Argentine crowd favorite Juan Monaco upended No. 3 seed Pablo Cuevas, of Uruguay, 7-6 (7-1), 6-7 (4-7), 6-4. The former top-10 star Monaco titled here in 2007 and was the '09 runner-up to Robredo.

Monaco will meet Almagro in Saturday's semifinals.

The 2015 Buenos Aires titlist will collect $91,050.