Canadian tennis star Milos Raonic had a disappointing start to his clay-court season Monday.

Raonic dropped a 6-2, 3-6, 6-3 decision to Spanish veteran Alberto Montanes in the first round of the Monte-Carlo Rolex Masters, his earliest exit of the season. It was Raonic's first match since he was forced to withdraw from the Sony Ericsson Open because of an ankle injury.

Facing the 31-year-old Spaniard, who was ranked 22nd in the world two years ago, Raonic quickly dropped the first set and trailed by a break in the second. He rebounded to win the second set but couldn't complete the comeback in the third.

Montanes will meet Serbia's Janko Tipsarevic, the seventh seed, in the second round of the ATP World Tour Masters 1000 event.

Raonic will next play in the ATP 500 event in Bracelona next week.