Jelena Ostapenko has gatecrashed the upper echelons of the Porsche Race to Singapore with her shock Roland Garros title in this week's update of the chase to make the BNP Paribas WTA Finals Singapore presented by SC Global.

The 20-year-old was already at No.25 thanks to a runner-up showing in Charleston and semifinals in Auckland and Prague, but she's firmly among the frontrunners now, zooming 21 spots to No.4. The Latvian has never previously played the WTA Finals - indeed, previously to this week she had never been ranked inside the WTA Rankings Top 30.

The pole position in the Race has been seized by Roland Garros runner-up Simona Halep. The Romanian languished outside the Top 20 before surging over a stellar clay-court swing, during which she also picked up her third Premier Mandatory title in Madrid and another runner-up plate in Rome - where she lost to Elina Svitolina, whom she has now dislodged from the top spot. However, the Ukrainian's quarterfinal run in Paris keeps her in the Race Top 3.

French Open semifinalist Karolina Pliskova retains her No.2 position, while quarterfinalists Caroline Wozniacki and Kristina Mladenovic fall one spot to No.5 and climb one to No.6 respectively. Further down, dramatic gains have been made by Timea Bacsinszky, whose first semifinal run of the season sees her leap 44 places to No.16, and Caroline Garcia, a Slam quarterfinalist for the first time and a climber of 13 spots to No.17.

Meanwhile, Roland Garros doubles champions Bethanie Mattek-Sands and Lucie Safarova have risen one spot to retake their Race first place from Chan Yung-Jan and Martina Hingis, whom the Czech-American duo beat in the semifinals en route to their fifth Slam title together.