A summary of Thursday's play at the US Open.
Serena, a six-times champion in New York who is seeded 17th, will start her campaign against Polish world number 60 Magda Linette and could face Venus in the third round before a possible fourth-round showdown with Romanian top seed Halep.
PHOTOS from the Wimbledon Championships matches played at the All England Lawn Tennis and Croquet Club, London, on Saturday
Russia's Daniil Medvedev remarkably reached his ninth final of the season as he defeated Stefanos Tsitsipas 7-6(5), 7-5 at the Shanghai Masters on Saturday.
Summary of sports events and persons who made news on Friday
A summary of sports events and sports persons, who made news on Wednesday
Top seed and defending champion Roger Federer battled past in-form Russian Daniil Medvedev 6-4, 4-6, 6-4 to reach the last-16 at the Shanghai Masters on Wednesday.
Images from Day 4 of the Wimbledon tennis championships played in London, on Wednesday.
US Open, the final Grand Slam of the season, starts Monday, August 28, at Flushing Meadows in New York.
The draw for the first Grand Slam of the season was made on Thursday and the top seeds could face some early tests of their credentials when play gets underway in Melbourne on Monday.
Images from Day 5 of the 2021 French Open, in Paris, on Thursday.
Maria Sharapova will be back in the US Open spotlight on Wednesday hoping she can come up with a winning encore to her electrifying first round victory over second seed Simona Halep.
A round-up of all tennis action on Saturday.
Form guide for American Serena Williams ahead of Thursday's US Open semi-final clash against Latvia's Anastasija Sevastova:
Angelique Kerber, who will reclaim the world number one ranking on Monday, breezed to a 6-2, 6-1 second-round victory over fellow German Andrea Petkovic at the BNP Paribas Open on Saturday.
IMAGES from the Australian Open on Tuesday.
Summary of sports events and persons who made news on Sunday
Images from Day 3 of the Wimbledon tennis championships played in London, on Wednesday.
Images from Day 3 of the French Open matches played at Roland Garros on Tuesday
A summary of Tuesday's play at the French Open.
IMAGES from the matches played during the Wimbledon Championships at the All England Lawn Tennis and Croquet Club, at Wimbledon in London on Thursday
Roger Federer began his 63rd consecutive Grand Slam tournament with a majestic 6-1, 6-3, 6-3 first-round win over little-known Bosnian Damir Dzumhur at Wimbledon in London, on Tuesday.
The returning Scot also announced his withdrawal from next week's Rogers Cup in Toronto.