TORONTO -- Canadian qualifier Brayden Schnur got a taste of professional tennis, even if it was a sour one.

Schnur, a 19-year-old from Pickering, Ont., made his ATP World Tour debut Tuesday at the Rogers Cup and was promptly eliminated in a 6-3, 6-3 loss to Italy's Andreas Seppi.

"He was just a little bit better at everything, really, than me," Schnur said. "He kept the balls deeper at the end of the court, pushed me back, made a lot more balls that I'm not used to seeing come back, and didn't let me attack so often, that's for sure, took away my weapons."

Schnur and Seppi waited out a rain delay of more than two hours before beginning their match on the grandstand court at Rexall Centre. Schnur said that didn't help his fatigue, but he acknowledged it being part of his learning process.

"Nerves are always in my system," Schnur said. "It slowly tires you out going in and out, in and out, warming up, having to cool down. But it's something that I'm learning to get used to."

Schnur got used to being the fan favourite during his qualifying matches over the weekend. Fans encouraged him with shouts of, "Come on, Brayden," against Seppi, but the home-country advantage wasn't enough against a veteran like Seppi.

"Obviously at important moments, he missed a few important shots," said Seppi, who advances to face Ivan Dodig, who upset 10th-seeded John Isner. "I knew (Schnur) could serve pretty well, and I think he didn't have so good percentage on the first serve, otherwise it would be for sure tougher. I think he can for sure play pretty well, especially on the hard courts. It was his first match, so I think he handled it really well."

Schnur plans to play a futures event in Calgary next week before returning to school at the University of North Carolina. He considered these few days in Toronto a benefit for his career.

"It's good to see what I can improve on," Schnur said. "I gained a lot of confidence in my game. I think I played a lot better, even though I lost."

The rain delay that stretched from the morning into the afternoon caused some schedule shifting, including Jack Sock and Jurgen Melzer being moved to an additional court. Once on it, Sock beat Melzer 6-1, 6-3 to set up another rematch against Canadian Milos Raonic.

Raonic beat Sock, who's from Nebraska, in straight sets at Wimbledon and then again last week at the Citi Open in Washington.

"I'm definitely excited for tomorrow," Sock said of facing Raonic. "The juices will be flowing. He got me in my home country last week, so I'm going to try to maybe get some revenge."

Sock's doubles partner, Vasek Pospisil, faced 12th-seeded Richard Gasquet in afternoon action. Pospisil is coming off a loss to Raonic in the Citi Open final.

In other early play, fast-rising star Nick Kyrgios beat Santiago Giraldo, 7-6 (3), 7-5 to set up a match with No. 8 seed Andy Murray, No. 11 seed Ernests Gulbis beat Joao Sousa 6-3, 6-4 and Yen-Hsun Lu beat Marcel Granollers 7-6(6), 7-5.

The main event Tuesday night features No. 2 seed Roger Federer against Canadian wild card Peter Polansky. In the late match, third-seeded Stan Wawrinka faces Benoit Paire.