Updated

Formidable Canadian Milos Raonic was a straight-set opening-round winner Tuesday at the 2013 U.S. Open.

The 6-foot-5 10th seed handled diminutive Italian Thomas Fabbiano, 6-3, 7-6 (8-6), 6-3, on a warm, breezy day at the USTA Billie Jean King National Tennis Center. The massive-serving Raonic unleashed 28 aces, compared to zero by the overmatched Fabbiano.

A big upset came when 30-year-old Argentine qualifier Maximo Gonzalez upended 14th-seeded 6-foot-8 rising Pole Jerzy Janowicz, 6-4, 6-4, 6-2. Janowicz reached his first-ever Grand Slam semifinal at Wimbledon last month.

Also on Day 2, 22nd-seeded German Philipp Kohlschreiber whipped 17-year-old American Collin Altamirano, making his ATP-level debut, 6-1, 6-3, 6-1, and 31st-seeded quality Frenchman Julien Benneteau got past Poland's Michal Przysiezny, 6-4, 5-7, 6-4, 6-4.