LUGANO, Switzerland - Iga Swiatek came from a set and a break down in both the second and third sets to make her first WTA Tour semifinal at just her third attempt at the Samsung Open presented by Cornèr, overhauling No.8 seed Vera Lapko 4-6, 6-4, 6-1 in two hours and four minutes.

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The 17-year-old made her WTA-level main draw debut at the Australian Open in January, winning a round both there and in Budapest in February. This week, having gained direct entry into a WTA tournament for the first time - Swiatek has received no wildcards in her career to date, whether qualifying or main draw - the Pole notched up her first Top 50 scalp in upsetting No.3 seed Viktoria Kuzmova to make her quarterfinal debut; and today recovered from missing 10 break points in a lost first set to fire 38 winners and 10 aces to eliminate the tournament's last remaining seed.

In a first clash between two recent junior standouts - Lapko was the 2016 Australian Open girls' winner, while Swiatek is the reigning Wimbledon girls' champion - it was the younger player who leapt out of the blocks, playing impeccable power and delivering a sequence of scorching backhand winners to break and lead 3-1.

But three no-holds-barred return winners got Lapko back on serve, and from there the Belarusian eked out a narrowly contested set via some supremely clutch serving of her own. Back at the site of her own breakthrough - Lapko made her maiden WTA semifinal in Lugano last year - the 20-year-old saved six break points in a nine-deuce game to level the scoreline at 4-4, and a further four to serve out the set.

Despite Swiatek impressing with both the quality and variety of her returns when she could lay a racquet on the Lapko delivery - a number of short slices proved particularly effective when juxtaposed with the teenager's usual hard-hitting approach - she could only watch as Lapko seemed to find the lines at the most crucial junctures.

With Swiatek overpressing as though to compensate, Lapko firmed up her lead to break immediately at the start of the second set, and move up 2-0 with her fourth ace. But the World No.115 came roaring back, diversifying her tactics with more frequent use of the dropshot, as well as a couple of judicious net approaches.

Swiatek's mental fortitude also shone through: having stormed through four games to lead 4-2, she once again fell victim to Lapko going all out on return to break back and level at 4-4. But with the match evenly poised, Swiatek moved up a gear and never let go. Following up her dropshots with clever passes and lobs, the teenager sealed the set with a backhand winner down the line.

Dropping serve at the start of the decider proved to be a mere blip: by now, Swiatek was anticipating Lapko's preferred striking patterns more effectively, and the Guangzhou, Tashkent and Luxembourg quarterfinalist was becoming increasingly error-prone. Weathering the storm of Lapko's heavy hitting, Swiatek kept her head to execute her own shots on big points: in contrast to the 10 break points she missed in the opening set, the second and third saw the former junior World No.5 snatch six of her eight chances. On her own delivery, raising her first serve percentage to 68%, Swiatek simply offered Lapko nothing: from 0-1 down, she would not face another break point.

Careening through the final six games in a row, Swiatek wasted no time in closing the match out with her most emphatic hold of the day, firing two aces and her 38th winner of the day to serve it out to love.

This time last year, Swiatek was ranked World No.692 and had played just 10 ITF World Tour events - and had only just made her debut at W25 level. Since then, her rise has been unstoppable. It could well see her crack the Top 100 after this week, depending on the results of other players in her rankings vicinity - or, if Swiatek is able to defeat either Kristyna Pliskova or Svetlana Kuznetsova to make her first final, she could simply guarantee it herself.