Canada's Eugenie Bouchard fell 7-6 (1), 6-1 to Zheng Saisai of China in the third round of the Qatar Open on Wednesday.
Despite the loss, Bouchard said a kind gesture from the hotel she was staying at in Doha made her feel better. Bouchard turns 22 on Thursday.
Always learning. At least the hotel made me feel better... 😊 pic.twitter.com/I5V9iJbhKo— @geniebouchard
Zheng had beaten Australian Open champion and top-seeded Angelique Kerber on Tuesday to advance.
Meanwhile, third-seeded Agnieszka Radwanska came through a tough first set before beating Monica Niculescu 7-5, 6-1 to reach the quarter-finals.
Radwanska, who was down a double break in the first set, struggled with her first serves. But as the match progressed, the Pole's superb shot-making gave Niculescu little chance of recovering.
"I think she has the best hands on tour, very tricky player and very uncomfortable to play against," Radwanska said of her Romanian opponent.
"I knew it was going to be tough and a long one. What can I say? She really made me play my best tennis, so I'm very happy to win that match in two sets."
Radwanska next plays ninth-seeded Roberta Vinci of Italy, who defeated Turkish wildcard Cagla Buyukakcay 7-5, 6-1 in the last match of the day.
Also advancing from the third round was fourth-seeded Garbine Muguruza of Spain, who beat Timea Babos of Hungary 6-2, 7-5.
However, fifth-seeded Petra Kvitova of the Czech Republic lost 5-7, 6-2, 6-1 to Jelena Ostapenko of Latvia.
Kvitova, a two-time Wimbledon champion, came from 3-1 down to win the first set, but Ostapenko continued to play with confidence. She hit 28 winners before wrapping up the match in one hour and 56 minutes.
Caroline Wozniacki of Denmark, seeded 13th, lost 7-5, 5-7, 6-3 to Elena Vesnina of Russia.