Venus Williams has yet to win on clay this season
Venus Williams told the umpire "I can't control God" after getting a time violation during heavy winds in a loss to Anna Karolina Schmiedlova in Parma.
The American, 40, took the first set 7-5 despite being 5-2 down to the Slovak.
But gusty conditions then forced her to take her time on serve, resulting in the time violation and a confrontation with the chair umpire.
"I'm just saying that wind blows and there is nothing I can do about that," she told the umpire.
"I can't control God, talk to him," the former world number one added, pointing a finger upwards before walking back to the baseline.
The match ended 5-7 6-2 6-2, with Schmiedlova sealing her fourth consecutive victory over the seven-time Grand Slam champion after two hours and 39 minutes.
Serena builds up for French Open with opening round win
Williams' sister Serena beat Italian teenager Lisa Pigato as she was given a late wildcard into the event after losing her first competitive match since mid-February at last week's Italian Open.
The 23-time Grand Slam champion needed an hour and eight minutes to win 6-3 6-2 against 17-year-old Pigato.
"Lisa played really well," Serena Williams said. "Her future is super-bright."
Pigato was born a fortnight before Williams, 39, won her sixth Grand Slam title at Wimbledon in 2003.
The qualifier, ranked 572nd, broke the American's serve in the first game of the match, before the world number eight quickly found rhythm and asserted her authority.
"She played really good and I needed to adjust to get back," top seed Williams said after her first victory on the red dirt in 2021.
"She handled the moment well, so I look forward to cheering for her in the future."
Williams will be going for a record-equalling 24th Grand Slam title, matching the number won by Australian Margaret Court, when the French Open starts on 30 May.
Meanwhile, British men's number two Cameron Norrie set up a second-round meeting in Lyon with US Open champion Dominic Thiem.
Norrie, who been impressive on both hard courts and clay this season, won 7-5 6-3 against France's Corentin Moutet in his opening match.
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