Caroline Wozniacki revealed at the WTA Finals in Singapore yesterday that she has been diagnosed with rheumatoid arthritis.

Two semifinal berths are set to be filled Thursday at the Singapore WTA Finals.

Elina Svitolina moved to 2-0 at the WTA Finals in Singapore. The last 3 US Open champions take the court Wednesday.

Caroline Wozniacki added her third title of the season.

Noami Osaka is closing in on another huge title.

Sloane Stephens has now lost four of her last six matches.

Interesting starts for (17) Keys vs. American countrywoman (LL) Pera, the struggling (9) Stephens vs. Pavlyuchenkova, (3) Kerber vs. the unpredictable Mladenovic, (10) Goerges vs. Konta, (7) Pliskova vs. (WC) Stosur, (12) Ostapenko vs. Rybarikova, (14) Muguruza vs. Makarova, and (2) Wozniacki vs. Bencic…

9 of the Top 10 on the WTA began the week in Wuhan.

It is the first time in the Open Era that the two top seeds have gone out before the quarterfinals at the US Open, and Wozniacki was the third Slam champion this week to lose on the new Louis Armstrong Stadium Court which is quickly becoming known as the “graveyard court.”

For the first time in US Open history an Extreme Heat Policy was implemented for men’s matches in addition to the women as temperatures neared 100 degrees at the USTA Billie Jean King National Tennis Center.

“I think it was a good match today,” Serena said afterwards. “We both played at a really high level. Only one person could win…I’m still at the very beginning. You know, this is a long comeback. I just began. I just started. Definitely at the very, very beginning. I’m getting there, and I’m going to just continue to work hard, and hopefully I’ll start winning more matches.”

Tough starts for (4) Kerber vs. Pavlyuchenkova who she is 6-6 career against, the wrist-addled (13) Keys vs. (WC) Mattek-Sands in an all-American, (9) Pliskova vs. Radwanska (winner to meet Konta), (6) Garcia vs. (WC) Azarenka, (8) Kvitova vs. the Serena-Gavrilova winner, (15) Mertens vs. Rybarikova who she has a losing record against, (5) Svitolina vs. (WC) Kuznetsova, and (2) Wozniacki vs. the Bertens-Vandeweghe winner…

The outrageous number of opening-round seeds vs. floaters match-ups includes (16) Kyrgios vs. (WC) Wawrinka, (11) Schwartzman vs. Edmund, (6) Cilic vs. Coric, (3) Del Potro vs. Nishikori, (14) Fognini vs. Johnson (winner to meet Shapovalov), (5) Dimitrov vs. Verdasco, (10) Goffin vs. Raonic, (4) Anderson vs. Rublev, (7) Thiem vs. the fast-rising Tsitsipas, (9) Djokovic vs. Chung, and (2) Zverev vs. Ferrer…

Serena Williams managed just one game against Johanna Konta Tuesday night in San Jose.

Compounding Wozniacki’s frustration was an invasion of flying ants during the match that saw insects flying in her ears and mouth during the competition.