Caroline Wozniacki reached her sixth career Dubai Tennis Championships semifinals when she defeated Catherine "Cici" Bellis 6-3, 6-2 on Thursday.
Wozniacki, who won the Dubai title in 2011, reached the Doha final last week. She's played nine matches in the last nine days.
Bellis, the youngest player in the draw at 17, scored the biggest win of her six-month-old pro career on Wednesday when she upset her first top-10 player, sixth-ranked Agnieszka Radwanska of Poland.
The American started the match confidently, jumping out to 3-1, but couldn't sustain the momentum.
"It was really fun for me to see what the highest level is (like)," Bellis said.
In a fight strictly from the baseline, Wozniacki won the next nine games to lead 6-3, 4-0.
"I stepped into the court a little bit after being down 3-1 and just tried to keep the pressure on her, make her think a little bit, not give her too many free points," said Wozniacki, who had her upper left leg wrapped.
She will play Anastasija Sevastova of Latvia in the semifinals. The 35th-ranked Sevastova reached her first semifinal of the season via a 6-4, 7-5 win over Wang Qiang of China.
"She's a player that mixes the pace up quite a bit," Wozniacki said of Sevastova. "She's definitely going to try and get me out of my own rhythm."
Seventh-seeded Elina Svitolina of the Ukraine improved her career record against Lauren Davis to 4-0 after defeating the American 6-0, 6-4 in the quarterfinals.
Svitolina, a semifinalist last year, won her fifth career title at the Taiwan Open this month. She'll play either top-seeded Angelique Kerber or Ana Konjuh of Croatia.