British duo Tim Henman and Greg Rusedski lost their first clay-court matches of 2006, crashing out of the Monte Carlo Masters in the first round.
Henman and Rusedski are being hit by harder draws
Henman looked uninspired and only managed to hold serve twice as he was defeated by world number eight Argentine Gaston Gaudio 6-1 6-3.
Rusedski fought back to level his match with Juan Ignacio Chela before crumbling to a 6-4 6-7 (5-7) 6-1 loss.
British number one Andy Murray plays France's Jean-Rene Lisnard on Tuesday.
Henman had meekly surrendered the opener as he struggled to land any first serves, getting just 47% in during the match as a whole.
The 31-year-old broke the world number eight twice in the second and even saved three match-points at 5-3.
But clay-court specialist Gaudio was too strong and broke Henman again to seal the victory. It was the first time Gaudio had beaten Henman in four meetings.
Rusedski put on a spirited display against Chela, another favourite on the clay, after losing a tight first set.
The 32-year-old British number two squandered a break in the second and missed a series of other break points as the set went to a tie-break.
A determined Rusedski clinched the breaker before losing his momentum and focus in the decider to lose to Chela for the second time this season.