BEIJING -- Jelena Ostapenko earned her second Top 5 win of the season after defeating No.4 Jessica Pegula 6-4, 6-2 in the Round of 16 at the China Open. The win is the Latvian's first over Pegula since 2015. 

China Open: Scores | Schedule | Draws

A semifinalist in 2017, Ostapenko will face Liudmila Samsonova in the quarterfinals. No.22 Samsonova came through a physical 2-hour and 55-minute effort to defeat Marta Kostyuk 6-4, 6-7(4), 7-5. Ostapenko leads their head-to-head 2-1. 

Highlights: Samsonova rallies from 3-0 down to stop Kostyuk 

"I think I always play quite well in China," Ostapenko said. "Finally tournaments are back here and with a lot of fans, which I like a lot.

"I think after US Open I had a little bit more confidence and I had really good preparation before US Open. I felt like some matches, even during the year, they were close matches. I was losing them but they were very close. I felt like at some point they have to go my way. It's working now." 

Ostapenko entered the match looking to avenge her three-set loss to Pegula earlier this season in Doha. There, Pegula saved match points on her way to a 6-2, 2-6, 7-5 victory. Pegula led the overall head-to-head 3-1, with Ostapenko's sole win coming on carpet in Quebec City in 2015.

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Coming off a quick turnaround from Tokyo after a run to her third final of the season, Pegula was looking to hand Ostapenko her fourth straight tournament exit at the hands of an American. After stunning then No.1 Iga Swiatek in the fourth round of the US Open, Ostapenko had not tallied back-to-back wins until Beijing. She bowed out to Coco Gauff at the US Open, Danielle Collins in San Diego, and Sofia Kenin in San Diego. 

After falling behind an early break in the first set, Ostapenko dominated Pegula from the baseline for the remainder of the match. After getting broken to trail 3-2, Ostapenko found her range and overpowered the American. Ostapenko's cumulative return pressure paid off in the set's final game. With Pegula serving up 40-0 to level the set at 5-5, Ostapenko took the game to deuce with a baseline flurry before Pegula double-faulted on set point. 

"I think there were a few important games in the first game, especially at 5-4 when it was 40-0 on her serve," Ostapenko said. "I was trying to stay in the game and to fight for every point. After I won that first set, I think in the beginning of the second set, I started pretty confident. 

Ostapenko continued her momentum in the second set, building a quick 3-0 lead before easily closing out the 78-minute match. 

"Just in general, I think I played well but it was not easy because the court was very slow and the rallies were super long. I felt the court is a bit slower than other tournaments."

"I felt like if you go for very dangerous shots it didn't really work on these courts," Ostapenko said." So I tried to open the point up and when I had the chance, just to finish it. Playing more angles worked pretty well."

Ostapenko finished the match with a sterling stat sheet, hitting 24 winners to just 11 unforced errors. Pegula finished with 12 winners to 12 unforced errors but served just 51 percent of her first serves in.