Aryna Sabalenka powered into her 11th semi-final of the year and a clash with Jessica Pegula after a 6-3, 6-3 win over Elena Rybakina at the Wuhan Open on Friday.

The world number one remains unbeaten in four tournament appearances at the event and will take a 20-0 record into her showdown with Pegula on Saturday.

American third seed Coco Gauff was also victorious, 6-3, 6-0 against Laura Siegemund to reach the last four in Wuhan for a second straight year.

Defending champion Sabalenka improved to 8-5 head-to-head against Kazakhstan's Rybakina, whose bid for a WTA Finals berth has taken a hit.

"Elena is a great player, very nice girl and always tough to play against," said Sabalenka, the US Open champion.

"We have a really huge history against each other, always great battles. She always pushes me to the limit to get the win.

"I’m super happy with the performance today."

A rock-solid Sabalenka claimed a timely break of serve in game eight on her way to forging a one-set lead in 43 minutes in temperatures above 30C.

Continuing to showcase some impressive all-court prowess, Sabalenka broke twice in the second frame to build a 4-1 advantage.

Rybakina, the eighth seed, narrowed the deficit by getting one of the breaks back but couldn’t stop Sabalenka from marching into the final four and extending her winning streak to 10 matches.

Sixth-seeded Pegula recorded her 50th win of the season with a 2-6, 6-0, 6-3 victory over Katerina Siniakova to reach a third consecutive semi-final, following Beijing and the US Open.

Pegula's last seven matches were all three-setters, contested within a 16-day period, and the American was successful in six of them.

"I guess I’m in really good shape," said the 31-year-old.

"I definitely don’t think I need to play any more matches or work on any physical stuff because I’ve been able to battle through these matches and play very well."

She added: "Obviously I wish maybe it was more straightforward for my mental and physical state.

"But if I win every match for the rest of my life in three sets I think I’ll be pretty happy."

Pegula’s left thigh was taped during her quarter-final but she told reporters it was just a precautionary measure and she felt “just a niggle” from playing too many long matches.

Unlike Pegula, Gauff has been breezing through her matches, and has dropped a mere nine games across three rounds so far in Wuhan.

The 21-year-old from Florida converted five of eight break points against Siegemund and completed the victory in 85 minutes.

“I think I had chances in the first set to even have a greater lead, so I think I just capitalised more on those chances in the second set,” said Gauff, who awaits Iga Swiatek or Jasmine Paolini in the final four.