The world number eight, who had a breakout season in 2009, had been suffering from elbow tendinitis before the tournament but refused to blame the injury for his 5-7 2-6 6-4 6-4 6-2 loss to the 23-year-old Spaniard.
"I didn't feel good at all," a visibly angry Soderling told reporters. "I don't know what happened I just didn't play well.
"I started terrible and finished terrible," he said, adding that the elbow injury had not affected his performance.
The Swede had held a 3-0 career record over the 113th-ranked Granollers before Tuesday's match. All of the matches, on three different surfaces, were played last year.
Soderling, who ended Rafa Nadal's four-year grip on the French Open last year, said he would return home immediately and did not have any plans to play again soon.
"I don't know," he said when asked when his next tournament would be. "Maybe not at all. But we will see.
"I played a terrible match today and am pretty disappointed."
(Reporting by Greg Stutchbury; Editing by Peter Rutherford)