Simona Halep surged to No 1 in the world for the first time and into the final of the China Open after beating Latvia's Jelena Ostapenko 6-2, 6-4 on Saturday
The Romanian's ousting of Spaniard Garbine Muguruza at the top of the women's game will be officially confirmed next week when the latest rankings are released.
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For Halep, who went into the semi-final on Beijing's outdoor hard courts as world No 2, victory was revenge after Ostapenko won their duel in the French Open final earlier this year.
"It’s very emotional. I think this is the first time I’ve cried on court. It’s amazing that I have done this," Halep said in her on-court interview.
"Thank you everyone for supporting me, of course my family and my team. It’s my special day."
The 26-year-old Halep, who is yet to taste grand slam success, will face either Caroline Garcia of France or Petra Kvitova of the Czech Republic in Sunday's final in the Chinese capital.
She was always in control against the world No 8 Ostapenko and put herself on the way to victory when she broke the talented 20-year-old in the first game of the first set.
Halep, the latest player to take the hot seat at the top of the women's game this year with Serena Williams becoming a mother, saw off former No 1 Maria Sharapova earlier this week in Beijing.