BUDAPEST, Hungary - No.1 seed Alison Van Uytvanck dealt with a difficult draw in style, saving two set points in the second set and navigating past Vera Zvonareva 7-5, 7-5 in a high-quality first-round encounter at the Hungarian Ladies Open.

The defending champion came into Budapest having notched up consecutive main draw wins just twice since her title run here last year - although one of those occasions, a fourth-round showing at Wimbledon via an upset of Garbiñe Muguruza, had been a fine showcase of Van Uytvanck's unique skillset.

The Belgian's wide-ranging repertoire was on display once again today. Over the course of a tightly contested first set, her dropshot in particular worked wonders - not only for the execution of the stroke itself, but Van Uytvanck's creativity and anticipation in following it up to finish points with passes, lobs and volleys.

Zvonareva, too, demonstrated the ability to think on her feet, hustling to steal a number of thrilling rallies she had seemed out of, and constructing smart points with careful changes of direction. The Russian managed to retrieve the first break deficit she faced to draw level at 4-4, but was broken again at 5-5 when she sent a forehand wide. Van Uytvanck then came up with her best game thus far to serve out the set.

The 24-year-old seemed to be on her way to an easy second set when she broke immediately and held a point for a 3-0 double-break lead, and then three more for 3-1. But a determined Zvonareva dug in to win both of those crucial games - despite falling and landing flat on her face as she stretched for a Van Uytvanck pass at one point - and instead levelled the score at 2-2 with a booming backhand return.

From 0-2 down, the World No.77 cantered through five consecutive games as a rattled Van Uytvanck lapsed into error. But facing two set points at 4-5, last year's winner found some much-needed magic in the nick of time, saving the first with a delicate backhand lob and the second with some fine net play.

For the second time in the set, the dynamic shifted quickly - and, this time, finally. From set points down, Van Uytvanck reeled off 16 of the next 18 points to complete a five-game streak of her own, accelerating over the finishing line and sealing victory with her fifth ace of the day. Up next in her quest to defend a title for the first time will be 17-year-old qualifier Iga Swiatek.

Elsewhere, Anastasia Potapova became the first player into the quarterfinals after a 6-2, 7-5 upset of No.6 seed Andrea Petkovic - the Russian's first win over a player who has been ranked inside the Top 10. "I was really waiting for this match because it was quite special," the 17-year-old informed the press afterwards. "When I was 10 years old I was watching [Petkovic] play the quarterfinals in all the big tournaments - she was an idol of my grandmother!"

Dominating with her forehand in particular and sending down six aces, Potapova broke Petkovic five times en route to a 6-3, 5-3 lead. Although she was unable to close the match out on her first opportunity, the German blasting a forehand to save a match point at 5-4, Potapova simply raised her intensity to break Petkovic again and serve out to 30 at the second time of asking.

"I was excited, I was not nervous at all," declared the Moscow River Cup and Tashkent finalist afterwards before correcting herself. "I mean, of course every player is nervous before the match - and for myself it's good when I feel a little bit nervous because I'm very focused on the court. If I'm not nervous and feel like I will win anyway I can play really bad, like in my first round [win over Heather Watson]." Up next for the World No.87 will be either No.4 seed Aleksandra Krunic or Sorana Cirstea.

Meanwhile, there were first-round wins for No.5 seed Ekaterina Alexandrova, who has now won 17 of her past 19 indoor matches but was forced to come from a set down before putting away 39-year-old qualifier Greta Arn 4-6, 6-1, 6-4; and No.8 seed Marketa Vondrousova, who sailed through one set and toughed out another for a 6-0, 7-6(6) defeat of qualifier Georgina Garcia Perez.

Anastasia Potapova in second-round action in Budapest (Hungarian Ladies Open/Peter Zador)