Serena was rumoured to have dated Dimitrov in the past, adding an extra layer of intrigue to the occasion.
Images from the US Open men's singles third round match at Flushing Meadows, New York, on Friday.
Poland's world number one Iga Swiatek swatted aside 25th seed Anastasia Pavlyuchenkova 6-4, 6-2 with a near-flawless performance to reach the round of 16 for a fourth straight year at the U.S. Open on Saturday.
Images from the men's singles action at the US Open on Sunday.
Images from Monday's Round of 16 women's singles matches at the US Open.
Carlos Alcaraz will be backed to extend his winning run at the Grand Slams to 16 matches following triumphant French Open and Wimbledon campaigns.
Images from the men's singles Round of 16 matches at the US Open on Monday.
Iga Swiatek was thrilled to see Ted Lasso lead Jason Sudeikis in the stands.
Madison Keys stunned third seed Jessica Pegula 6-1, 6-3 in an all-American clash
World number one Jannik Sinner's bid for a second Grand Slam title continued to gain momentum as he thumped Christopher O'Connell 6-1, 6-4, 6-2 on Saturday to reach the US Open fourth round.
China's Zheng Qinwen is bidding to become the fourth woman to win Olympic gold and the US Open title in the same year
Images from the US Open women's singles third round matches, at Flushing Meadows, New York, on Friday.
Images from the US Open men's singles second round matches, at Flushing Meadows, New York, on Wednesday.
The real fashion standout is Carlos Alcaraz, the 20-year-old sensation, who has adopted a unique sleeveless look.
'The romanticism of late night tennis in New York, it's time to move past that'
Climate protesters halted the US Open women's semi-final between American Coco Gauff and Czech Karolina Muchova for nearly an hour on Thursday.
Images from the US Open women's singles second round matches, at Flushing Meadows, New York, on Wednesday.
Images from the US Open women's singles second round matches, at Flushing Meadows, New York, on Thursday.
'I was so close to winning a Grand Slam. I want to make sure that my body is going to have the time it needs to come back, so please bear with me.'
Germany Jan-Lennard Struff has also withdrawn from the US Open, the USTA said.
As he continues to live his dream, Novak Djokovic is also staking his claim to the mantle of greatest tennis player of all time.
Novak Djokovic has no intention of passing the torch to the next generation just yet.
Shelton first through to quarters as action heats up at U.S. Open
The former world number one plans to play more of a full schedule next year and will work to improve on her serve, which she said let her down particularly in the first and third sets.
IMAGES from Day 1 of the US Open played Flushing Meadows, New York, United States, on Monday.
Wawrinka won the Australian Open in 2014, the French Open in 2015 and the US Open in 2016. He is a 16-time winner on the ATP Tour.
Novak Djokovic's bid for a record 25th Grand Slam title kicked off on Monday with an easy win over qualifier Radu Albot in the US Open first round.
Images from the US Open men's singles second round matches, at Flushing Meadows, New York, on Thursday.
The 23-year-old released a short social media statement on Saturday to thank her fans for their support over her decision to withdraw from the French Open following a dispute over her refusal to attend press conferences.
The Spaniard's withdrawal means Medvedev will be top seed at the March 1-7 event, which also features top-10 players Stefanos Tsitsipas and Alexander Zverev.
At the age of 36, Novak Djokovic is the fourth oldest Grand Slam champion of the Open era.
In winning his third New York crown, he joined 14-times Grand Slam winner Pete Sampras in third on the all-time list, trailing only Roger Federer (20) and Rafael Nadal (17).
Fourth-ranked Carlos Alcaraz and Norway's world number seven Casper Ruud also have a shot at top spot.
Defending US Open champion Rafael Nadal retired from his semi-final against Argentine third seed Juan Martin del Potro on Friday with right knee issues. The world number one was trailing 7-6(3), 6-2 when he decided to call it a night.
Serena Williams crushed older sister Venus 6-1, 6-2 in a shockingly subdued third round clash at the US Open on Friday to stay on track for a record equalling 24th Grand Slam title.
A summary of Wednesday's action at the US Open.
'I'm so humbled by the continuous support from my fans in Rome and I look forward to making my return soon.'
It was a battle of wills out on court at the USTA Billie Jean King National Tennis Center on Tuesday, with the proceeding stretching to nearly 5 hours -- four hours and 50 minutes precisely.
Andy Murray may have been the forgotten man at the US Open but gave the crowd and Stefanos Tsitsipas a match to remember, forcing the third seed to grind out a 2-6, 7-6(7), 3-6, 6-3, 6-4 win on Monday and avoid the opening round shocker.