Venus Williams battled bravely before bowing out of the US Open on her return to Grand Slam tennis on Monday as Spanish ace Carlos Alcaraz stormed into the second round with a dominant opening win.

The second full day of action in New York saw all eyes turn to the Arthur Ashe Stadium's night session, where the 45-year-old Williams lost in three sets to 11th seed Karolina Muchova.

Williams only returned to competitive tennis in July following a 16-month absence from the sport and had been granted a wild card into the main draw at Flushing Meadows.

But hopes of a fairytale run -- 28 years after her debut in the tournament -- ended in a 6-3, 2-6, 6-1 loss to Muchova, who was not even born when Williams turned professional in 1994.

"I didn't win today but I'm very proud of the way I played

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