PRAGUE, Czech Republic - No.6 seed Katerina Siniakova powered into her first quarterfinal of the season in front of home fans at the J&T Banka Prague Open, blazing 21 winners and dismissing wildcard Jana Cepelova 6-1, 6-3 in one hour and six minutes.

Last year had been the Czech's best to date, seeing her finish both at a career-high of World No.31 in singles and as the No.1 doubles team in the world with Barbora Krejcikova. However, the 22-year-old has had a surprisingly fallow 2019, and came into her home tournament sporting just a 2-9 record in WTA main draws, having only won consecutive matches in qualifying for Sydney in January.

But there has been no sign of any struggles this week so far as Siniakova has stormed through the draw, conceding only six games en route to the last eight. Today, the World No.44 was in supreme form against an opponent she had previously beaten three times in three encounters, with her backhand in particular working a treat.

Former World No.50 Cepelova had garnered a reputation as an upset artist in her prime, with three Top 3 victories to her name: Serena Williams at Charleston 2014, Simona Halep at Wimbledon 2015 and Garbiñe Muguruza at Wimbledon 2016. But the Slovak has sunk back into the ITF World Tour over the last two years, with her ranking now down to No.232, and today found her bidding for her first WTA quarterfinal since her last-four run at Istanbul 2017.

Cepelova displayed flashes of her best form, landing some forehand blows to break Siniakova in the fourth game of the first set and finding pockets of success with the slice and dropshot as she battled to stay in the second set. But in the main, Siniakova was irresistible.

The two-time WTA titlist delivered a masterpiece of an opening act, committing just one unforced error while striking an array of winners - in particular, relentlessly punishing the short Cepelova delivery. The 25-year-old failed to hold serve at all in the first set, and indeed only won six points behind it in total.

Siniakova went from strength to strength as the second set got under way, breaking Cepelova in the second game and raining down three aces to move out to a 3-0 lead. It was only at this point that the 2014 Charleston runner-up began to make matters more competitive, finding the range on her forehand and better anticipating the Siniakova dropshot to notch up three service holds.

But it was too little, too late - and in any case, throwing variety at Siniakova simply gave the reigning Roland Garros and Wimbledon champion an opportunity to show off more of her repertoire. The 22-year-old delighted with her reflexes at net on a number of occasions, and her finesse was in full flow as she out-manoeuvred Cepelova with a backhand dink to kick off a love hold that sealed the match.

Siniakova moves into her fourth career quarterfinal in Prague - a stage at which she has fallen in each of the past two years, to Barbora Strycova in 2017 and to Petra Kvitova in 2018. Bidding to make the semifinals for the first time since 2015, either compatriot and No.9 seed Strycova or Jessica Pegula will stand in her way tomorrow.

Earlier, wildcard Karolina Muchova also delighted the home crowd with a battling 6-4, 3-6, 7-6(2) victory over Jennifer Brady in two hours and 32 minutes, while another epic three-setter found Natalia Vikhlyantseva triumphing 6-4, 2-6, 7-5 over 18-year-old Anastasia Potapova in an all-Russian derby.