Venus Williams, of the United States, returns during a first-round match against Rebecca Marino, of Canada, at the Citi Open tennis tournament in Washington, Aug 1, 2022. (CAROLYN KASTER / AP)

Venus Williams was disappointed not to give the crowd the win they wanted on Monday after the former world number one suffered an opening round defeat at the WTA 250 Citi Open on her return to singles action after almost a year out.

The 42-year-old, playing singles for the first time since last August, lost 4-6 6-1 6-4 to Canadian qualifier Rebecca Marino under the lights in Washington, DC.

"Just a little rusty," Williams told reporters. "I really put myself in good positions in the third set, too. Just trying to shake off some rust. That's just to be expected. All I can do is just play another tournament and play better.

"I wish I could have pulled this match through for the crowd and for the tournament. But (it) doesn't always work out."

READ MORE: Venus Williams set for singles comeback in Washington

Venus Williams (left) of the United States, and Rebecca Marino (right) of Canada, shake hands after a first-round match at the Citi Open tennis tournament in Washington, Aug 1, 2022. (CAROLYN KASTER / AP)

The seven-times Grand Slam winner is set to play in WTA 1000 events in Toronto and Cincinnati over the next two weeks.

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