Ninth seed Marin Cilic has suffered a surprise first-round defeat at the Italian Open to Guillermo Garcia-Lopez.

Cilic was broken in the opening game of the match and went on to squander four break points of his own before Garcia-Lopez clinched the first set 6-4.

The US Open champion was forced to defend six break points at the start of the second, but Garcia-Lopez would not be denied as he managed to take a 4-2 lead on his way to closing out the contest 6-4 6-3.

Waiting for the world number 28 in the second round will be either Martin Klizan or Alexandr Dolgopolov.