Former top-10 star Tommy Robredo posted an upset victory Monday at the Swedish Open.

The wild card Spanish veteran, coming off a lengthy injury layoff, upended eighth-seeded Adrian Ungur of Romania 6-4, 6-2 on the red clay at Bastad Tennis Stadium.

Robredo was the Bastad champion in 2006 and 2008.

Additional Day-1 wins came for Estonian Jurgen Zopp, Czech Jan Hajek and Italian Simone Bolelli.

This week's top seeds are Spanish stars David Ferrer and 2010 champion Nicolas Almagro. The 2007 winner Ferrer will meet Bolelli in his opener.

Ferrer was last year's runner-up to Swedish two-time winner Robin Soderling, who is not defending his title this week, and beat Almagro in an all-Spanish finale here in '07.