NEW YORK, NY, USA - Garbiñe Muguruza's shock exit to Anastasija Sevastova whittled down the number of contestants in the US Open's No.1 ranking sideshow to three: Serena Williams, Angelique Kerber and Agnieszka Radwanska.
As the tournament enters its opening weekend wtatennis.com updates the state of play in the race for top spot...
Serena Stays On Course: Serena Williams entered the US Open as the WTA World No.1 ranked player, a distinction she has held since February 18, 2013 - a streak that will extend to 186 consecutive weeks through the US Open, tying the WTA record for most consecutive weeks at No.1 held by Stefanie Graf (186 weeks, August 17, 1986 through March 10, 1991).
Overall, the fortnight of 2016 US Open is Serena Williams' 308th and 309th weeks at World No.1 - however she could lose her status at the top of the rankings at the completion of the US Open - with Angelique Kerber and Agnieszka Radwanska having a shot at deposing the 22-time Grand Slam champion and bidding to become the 22nd woman to sit atop the WTA Rankings since their introduction in November 1975
Williams held a 190 point advantage over Angelique Kerber going into the US Open but when last year's points are dropped (Williams reached SF, Kerber fell in 3r in 2015), Kerber has a 460-point advantage. Therefore, to remain at No.1, Williams will need to at least reach the semifinals and possibly advance further:
- If Kerber reaches the US Open quarterfinals by defeating Petra Kvitova today, Williams will need to reach the final to have a chance at keeping the No.1 ranking
- If Kerber advances to the US Open final, Williams will need to lift her 23rd Grand Slam title to hold on to the top spot.
Williams' ranking points have come from seven tournaments in the last 52 weeks - 2015 US Open (780), Australian Open (1300), Indian Wells (650), Miami (120), Rome (900), Roland Garros (1300) and Wimbledon (2000).