In her first match since the U.S. Open, Eugenie Bouchard wins in China

The last time Canadian tennis fans saw Eugenie Bouchard, she was in some distress, wilting in the New York heat and humidity at the U.S. Open in a fourth-round loss to Ekaterina Makarova of Russia.

The 20-year-old from Montreal returned Tuesday at a new top-tier WTA Tour event in Wuhan, China and after a slow start, finally pulled together her attacking game and prevailed 4-6, 6-3, 6-4 over Germany's Mona Barthel. The heat and humidity were similar, although playing a night match was a definite help. This time, the Canadian was ready for it.

Bouchard had a bye in the first round before playing Barthel. She will meet American Alison Riske in the third round. And as the top players continued to fall in China, a projected quarter-final round meeting with world No. 1 Serena Williams once again cannot come to pass.

Once again, it is Williams who won't make the date.

This inaugural tournament, for which the WTA Tour schedule was shuffled and compressed and which has come to be in large part because Wuhan is the hometown of Chinese superstar Li Na (who inconveniently retired over the weekend), has seen its top players fall like dominos in the first three days.

Of the 16 original seeds in the 56-player draw, only five remain after the second round: Bouchard, Petra Kvitova (No. 3) Maria Sharapova (No. 4), Angelique Kerber (No. 7) and Caroline Wozniacki (No. 8).

The biggest culprit seems to be a virus, a bug that's been going around. Williams was the most extreme victim of it; she retired during her match against Alizé Cornet of France Tuesday, about to serve for the first set at 6-5, when she felt dizzy and nauseous. No. 2 seed Simona Halep, short on confidence after a trying summer on the North American hard courts, lost to Spain's Garbiñe Muguruza in three sets Tuesday in her first match since the U.S. Open.

It was Bouchard's first match since New York as well. She began slowly against Barthel, who despite the height, blonde braid and visor is Bouchard's polar opposite.

The German flies under the radar much of the time, even though she will occasionally pop up and upset a very good player. She has been without a coach for long periods during her pro career. She wears whatever clothes can be provided for her and looks as mismatched as Bouchard is put together by Nike.

But Barthel is as smooth as Bouchard is effortful in her ball-striking, and just as capable of playing a match on her own terms and firing winners. She did that in the first set. The German staked out a 2-0 lead in the final set, with a couple of opportunities to make it 3-0, before her lack of consistency got the better of her. Bouchard started firing, changing directions and hitting down the line, and basically refused to miss.

The Canadian is in China without coach Nick Saviano; the only people cheering her on in a tiny support section (by Bouchard standards) were conditioning coach Scott Byrnes and a hitting partner.

Sharapova and Wozniacki are the two seeds remaining in her half of the draw. But she would face neither until the semi-final. So it could turn out to be an invigorating week for Bouchard as she begins the final chunk of her 2014 season and tries to solidify a spot in the year-end championships in Singapore next month.

In other Canadian tennis news out of China, Vancouver's Vasek Pospisil won his first match on the Asian swing, defeating big-hitting Russian Teymuraz Gabashvili 6-3, 6-4 in the first round of another new event in China, this one in Shenzhen.

Pospisil, the No. 7 seed, will face veteran Juan Mónaco of Argentina in the second round.