Olga Puchkova knocked out No.2 seed Sloane Stephens, 75 63, in the first round of the Citi Open on Monday.
WTA Staff

WASHINGTON DC, USA - The first day of the Citi Open brought with it the first major upset, as Olga Puchkova bundled out No.2 seed Sloane Stephens in straight sets.

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Despite being dressed from head to toe in neon orange, there were few bright moments from Stephens, who, in her first match since Wimbledon, struggled throughout for consistency on her serve and groundstrokes.

The American's rustiness was apparent from the outset as she slipped 3-0 behind in the blink of an eye, prompting the crowd to try and rouse their compatriot. Briefly, the tactic worked, as Stephens held serve in dominating fashion then broke Puchkova, but inconsistency struck again as a few unforced errors and an untimely double fault gifted the break back.

Puchkova continued to look the more assured in the second set, taking full advantage of her opponent's troubles to open up a 3-1 lead. As in the opener, Stephens battled back gamely, but the World No.88 was not to be denied, closing out a 75 63 win after an hour and a half on court.

"I just didn't play that well and wasn't feeling the ball great," Stephens said. "I would say that I'm a pretty consistent player - I don't really hit balls all over the place, that's not really how I play - but today there were some that I really couldn't believe it went that far out."

Puchkova's reward for knocking out the World No.15 - the fourth Top 20 win of her career - is a meeting with Paula Ormaechea, who brushed aside wildcard Beatrice Capra, 61 61.

Facing the winner of that match in the quarterfinals could be the upwardly mobile Andrea Petkovic. After an injury-ravaged 2012, Petkovic started the season barely inside the Top 200, but, on the back of some promising showings on the clay, is now sitting at No.64.

With few points to defend for the rest of the summer, Petkovic should be back inside the Top 50 before the US Open, and she edged closer to that target with a 62 75 win over Jessica Pegula on Monday.

On the other side of the draw, defending champion and No.7 seed Magdalena Rybarikova came from a set down to defeat Christina McHale. Rybarikova was unseeded last year and admitted in the interview following her 26 64 62 victory that the expectation levels have been raised a notch on her return.

"I'm feeling a bit of pressure coming back as champion and I started very badly," Rybarikova said. "But I always believed I could win this match and when I had some chances, I took them.

"I started to find my game in the third set and was really happy with how I was playing then. Hopefully I can keep this up in my next match because I love it here and hope to go far again."