PALERMO, Italy - Lucky loser Liudmila Samsonova powered into her maiden WTA Tour quarterfinal at the Palermo Ladies Open with a 6-2, 7-5 upset of No.4 seed Tamara Zidansek in one hour and 38 minutes.

"Everything was so good!" exclaimed a delighted Samsonova afterwards - except the weather, with temperatures pushing 30 degrees. "I hate to play at this time," she admitted. "It's so hot - but we survive!"

The Russian, who made her Grand Slam main draw debut this May after qualifying for Roland Garros and picked up her first WTA-level victory last week in Lausanne over Pauline Parmentier, had lost in qualifying this week to Amandine Hesse. However, Samsonova said that after that defeat, she had begun to "understand a lot" about how to play - and she displayed impressively controlled power to make the most of her second chance, notching up a second win over Zidansek in as many meetings this year, having also defeated the Slovenian 6-3, 4-6, 6-3 in Doha qualifying in February.

The first set was more closely contested than the scoreline might indicate, with the final six games of the opening act all featuring at least one break point. However, it was Samsonova who proved to have greater command of her aggressive game when she needed it, coming up with bold striking to come out on top of a break-heavy passage of play.

The 20-year-old - for whom these are home courts of sort, having lived in Italy since she was one year old and competed under its flag until last year - was particularly dangerous from the forehand wing, with a number of inside-out winners flowing from her racquet. The crucial game turned out to be her hold for 4-2, one that interrupted a sequence of four breaks: Samsonova staved off two break points, one with a dropshot that clipped the line, and came through with consecutive unreturnable serves. Two games later, more clutch serving had the first set in her pocket.

In full flow, Samsonova's level rose even higher to create her own luck in the second set. Three consecutive massive strikes garnered her immediate break points - and she was rewarded with a mishit dropshot winner to capture the game. But cruising at 6-2, 3-1, the World No.144 wobbled with a tentative volley and some forehand errors - and Zidansek pounced.

The Nurnberg runner-up had been somewhat hit-and-miss to this point, but tightened up her game to drastically reduce her own loose errors to reel off three games in a row. With Zidansek's level raised, it was to Samsonova's immense credit that she was able to halt the 21-year-old's momentum - her hold for 4-4 was not only supremely impressive in the context of the scoreboard but also featured some of her finest winners of the day - and then to come through a nailbiting dénouement to the contest.

Serving at 4-5, Samsonova gutted out another excellent hold after battling through four deuces, again finding that aggression paid off. By contrast, after coming so close to levelling the match, two-time Bol 125K champion Zidansek conceded the game with an underwhelming forehand slice error.

With Zidansek deflated and Samsonova rejuvenated, the final two games were a romp home for the younger player, who roared through 10 of the final 11 points to set up a last-eight clash with either Lausanne champion Fiona Ferro or wildcard Giulia Gatto-Monticone.