The US Open has been rocked by yet another huge upset.
No 4 seed Stefanos Tsitsipas has been knocked out of the grand slam tournament after suffering a shock defeat to Colombian qualifier Daniel Galan in the first round on Tuesday.
Galan, who sits at No 94 on the ATPrankings, stunned the Greek phenom 6-0, 6-1, 3-6, 7-5 to progress through to the second round, the first time he has achieved the feat at Flushing Meadows.
Tsitsipas' performance in the first two sets could only be described as dreadful – the 24-year-old was marred by dozens of unforced errors as Galan repeatedly broke his serve.
The 2021 French Open finalist, who at one stage lost 11 consecutive games, rediscovered some momentum in the third set, but Galan booked his place in the round of 64 by winning the fourth.
And then she added: "I'm going to stay vague, because you never know."
When she announced three weeks ago she was ready to move on from being a tennis player, Williams indicated the US Open could be it for her, but she never explicitly said it would be.
Elsewhere, Daniil Medvedev had an easy start to his US Open title defense, beating Stefan Kozlov 6-2, 6-4, 6-0.
Nick Kyrgios romped into the second round after crushing his doubles teammate Thanasi Kokkinakis in straight sets 6-3 6-4 7-6.
Former US Open champion Stan Wawrinka has hinted that retirement is just around the corner after he was forced to abandon his first round match against France's Corentin Moutet.
Two-time grand slam champion Simona Halep was knocked out of the tournament after suffering a shock defeat to unseeded Ukrainian Daria Snigur.
Canadian tennis star Bianca Andreescu powered past France's Harmony Tan into the second round, while British icon Andy Murray marked the 10th anniversary of his maiden grand slam triumph with an impressive straight sets win over Argentina's Francisco Cerundolo.
