NEW YORK — Eugenie Bouchard was blunt when assessing her inconsistent performance in her second-round loss at the U.S. Open on Thursday.

After rolling through three qualifying matches and posting an easy win in the first round, the native of Westmount, Que., lost 6-4, 6-3 to Marketa Vondrousova of the Czech Republic in the second round of the U.S. Open on Thursday.

While Bouchard has earned some praise for a recent improvement in her results after tumbling down the rankings in previous years, the world's 137th-ranked player struggled against the 103rd-ranked Vondrousova.

"Yeah, on the court, I really didn't feel like myself," Bouchard said. "That's very disappointing, considering how good I felt in my last couple matches. Yeah, I mean, I played like (expletive)."

"I think I'll have to take a lot of positives from the past couple weeks," she added. "Although I'm very disappointed with today, I've been playing matches, and that's what I feel like I need."

The Czech player broke Bouchard six times in the match, including the final game. Bouchard, who was once ranked No. 5 in the world, won just 59 per cent of her points on first serve.

Bouchard made 32 unforced errors, while Vondrousova made 25 and also gave up three breaks to the Canadian.

"Lefties are always tough," Bouchard said of her opponent. "It's a different spin. You don't see it often. She got a lot of balls back, made me feel that pressure kind of. But there were like 10 things I could have done better, so... it's more about me."

The 24-year-old Bouchard was the only Canadian in the women's singles draw.

Ottawa's Gabriela Dabrowski had a full schedule at the U-S Open on Thursday, winning both of her first-round doubles matches.

Dabrowski and Mate Pavic of Croatia downed American duo Jamie Loeb and Noah Ruben 6-0, 6-4 in mixed action, then she earned a 6-2, 6-7 (5), 6-1 win with Chinese partner Yifan Xu over Spain's Lara Arruabarrena and Renata Voracova of the Czech Republic in women's play.

Vasek Pospisil of Vancouver and partner Fernando Verdasco of Spain withdrew from a men's doubles match later Thursday.

Denis Shapovalov of Richmond Hill, Ont., and Milos Raonic of Thornhill, Ont., the two remaining Canadians in singles, play third-round matches on Friday.