Vancouver's Vasek Pospisil lost his career debut at the Monte Carlo Masters on Monday, falling 6-2, 6-2 in the first round to experienced clay-court player Roberto Bautista-Agut of Spain.
The 29th-ranked Pospisil lacks clay-court experience and paid the price against his 45th-ranked opponent who grew up playing on the surface.
"There's a lot you can learn from every loss," said Pospisil. "This one was more about my lack of clay experience, I need to get used to the surface. Working on my movement will help a lot, it's something I can improve."
Eighth seed Milos Raonic of Thornhill, Ont., had a bye in the first round and will face either Argentina's Federico Delbonis or Taiwan's Lu Yen-Hsun in the second round on Wednesday.
Pospisil was competing in only his seventh top-level match on clay and now stands 1-6 on the surface. His only victory came in a Davis Cup tie against Ecuador in 2011.
Pospisil hasn't played much since the Australian Open due to a back injury.
"Considering how little I've played in general, this was not so bad," said Pospisil. "He played extremely well and didn't miss any balls. I played well on my forehand but obviously clay is not my natural surface.
"There was really not much I could have done out there."
Pospisil, who committed 18 unforced errors in the opening set, admitted he came to the court with low expectations.
"I didn't have too many expectations, I've been dealing with a couple of injuries and only played points on clay for the first time yesterday."
The Canadian said that while he did not want to go into detail, his back felt fine during the match. Pospisil will move onto Bucharest and Munich over the next few weeks as the French Open buildup continues.
Elsewhere, Fabio Fognini of Italy was two points away from defeat before rallying to beat Joao Sousa 5-7, 7-5, 6-4.
Sousa led 5-2 and 30-0 on Fognini's serve, but the Portuguese player lost his composure and then started complaining to the chair umpire at the end of the second set and midway through the third.
"I'm not happy today. I was I think a bit lucky," Fognini said. "It was a really difficult match."
The 10th-seeded Fognini, who lost to title-holder Novak Djokovic in last year's semifinals, was the highest seeded player in action Monday in the clay-court tournament.
Fognini failed to serve out the first set at 5-4 and then his game fell apart.
"I was completely without energy, without power in my legs," he said. "I have no idea what happened."
After Fognini had served out the second set, the crowd jeered Sousa — who had received a warning during the first set. At 3-2 down in the third, Sousa continued to grumble, saying "it's a joke, it's a joke."
Fognini will play Bautista Agut in the next round.
Later in the day, 11th-seeded Tommy Robredo of Spain beat Belgian qualifier David Goffin 6-4, 6-1.
In other first-round matches, there were victories for Philipp Kohlschreiber of Germany, Czech players Radek Stepanek and Lukas Rosol; and Spaniards Albert Montanes, Albert Ramos and Pablo Andujar.
Rosol beat Evgeny Donskoy 7-5, 6-1; Kohlschreiber won 6-3, 6-4 against Simone Bolelli; Stepanek thrashed Ivo Karlovic 6-1, 6-2; Ramos beat Jarkko Nieminen 6-2, 7-5 and Andujar downed Edouard Roger-Vasselin 2-6, 7-5, 7-6 (5).
On Tuesday, Djokovic plays Montanes in the second round. On Wednesday, eight-time champion Rafael Nadal of Spain faces Gilles Simon or Teymuraz Gabashvili, and fourth-seeded Roger Federer takes on Stepanek.