Roddick, Hewitt, Coria Exit at ATP Masters Series-Canada

Roddick's former coach and current ESPN sideline commentator Brad Gilbert says the former No. 1 panics with his net game when under pressure, and sure enough that happened on a huge point with Roddick serving at 5-6, 15-30 in the first set. Instead of sticking with his meat-and-potatoes baseline game while down in the game, Roddick tried to surprise the Frenchman with a serve-and-volley attack, popping the ball up and allowing Mathieu plenty of time to throw a topspin lob over his head.

That point led to the break and the first set, with the wheels totally coming off in the second set for Roddick after Mathieu raced to a 3-0 lead over the frustrated American before eventually clinching victory.

"I thought he played great," said Roddick, who mustered only three aces to the Frenchman's 14. "I think he served really well tonight. You know -- a lot of credit to him. He didn't let me settle in and try to find my bearings. He really took it to me so I was playing reactive instead of active."

Roddick struggled with the faster conditions compared to those at his title-winning run last week in Washington.

"It just felt totally different out there than it did two days ago," Roddick said. "The court, the balls, they're all a little bit different. I just didn't adjust. It's a different ball. I just didn't feel like I was doing anything real comfortably out there."

Mathieu said Roddick isn't his top scalp, but is up there somewhere.

"I've already beaten (Pete) Sampras and (Marat) Safin, but it's definitely one of my best matches," Mathieu said. "The ball is really light and moves a lot here. You just have to adapt."

The event lost a total of five seeds on the day, with No. 2 Lleyton Hewitt retiring with a stomach illness against French qualifier Florent Serra, No. 7 Guillermo Coria held to only five games by former No. 1 and US Open runner-up Juan Carlos Ferrero, No. 13 Ivan Ljubicic volleyed out in three sets by unseeded American Taylor Dent, and No. 14 Radek Stepanek straight-setted by Swede Robin Soderling.

Seeded players successfully navigating first-round matches were (1) Rafael Nadal (d. Spanish countryman and former No. 1 Moya in three), and (12) Thomas Johansson (d. Karlovic).

"I only have little bit cramps in the beginning of the third (set)," said Nadal who called for a trainer with hand cramps against Moya. "But after, I feel good. Sometimes I have this problem, but is not important problem. Normally (it) come for two games or little bit time, and after go out."

Moya was complimentary of the player he has helped along since his early days on tour.

"To be honest, I didn't expect him to be that good so early," Moya said. "I think there was a beast inside of him, and I think the one who woke up the beast was (Andy) Roddick in the Davis Cup tie."

Unseeded players into round two were Czechs Tomas Berdych (d. Melzer) and Jiri Novak (d. Andreev 6-1 in the third), German Nicolas Kiefer (d. Massu), Frenchmen Sebastien Grosjean (d. Srichaphan in three) and qualifier Arnaud Clement (d. Acasuso from a set down), Belgian Xavier Malisse (d. (WC) Dancevic), Dane Kenneth Carlsen (d. (WC) Steckley from a set down), Moroccan-back-from-injury Younes El Aynaoui (d. F.Lopez), and Spaniard Dave Ferrer (d. Santoro from a set down).

Scheduled for Wednesday play are Max "The Beast" Mirnyi vs. "Grinning" Greg Rusedski, (Q) Bjorkman vs. (4) Agassi, Grosjean vs. (15) Gasquet in an all-French old-guard-vs.-new, (1) Rafael "The Prodigy" Nadal vs. Ricardo Mello "Yello," Taylor "Acci-" Dent vs. Kiefer, (6) Gaudio vs. Carlsen, Mathieu vs. (Q) Clement in another all-French old-guard-vs.-new, Ferrero vs. Ferrer in an all-Spanish, (12) T.Johansson vs. Xavier "X-Man" Malisse, Mario "Baby Goran" Ancic vs. (Q) Serra, Berdych vs. (5) Davydenko, El Aynaoui vs. (11) Robredo, Pavel vs. (8) Puerta, Olivier "The Roach" Rochus vs. Soderling, Novak vs. Dominik "The Dominator" Hrbaty, (9) Nalbandian vs. Beck, and in doubles highlights Argentines Nalbandian/Puerta vs. (3) Knowles/Nestor, and (5) Paes/Zimonjic vs. Israeli sleepers Erlich/Ram.