Serena's US Open implosions

Six-time US Open champion Serena Williams has been embroiled in her share of controversies at Flushing Meadows. AFP Sport looks at three Williams outbursts in the wake of her clash with umpire Carlos Ramos in a loss to Naomi Osaka in Saturday's final.

2009: Semifinal vs Clijsters

Williams streaked into the US Open having won the Australian Open and Wimbledon that year and chasing a second straight title in Flushing Meadows.

In the semifinals she was up against Kim Clijsters, a former rival who had taken off nearly three years to have her first child and had returned to the sport just weeks before.

Unranked and unseeded Clijsters won the first set with Williams receiving a warning for racquet abuse as she vented her frustration.

Williams was serving to force a tiebreaker at 5-6 in the second set when she was called for a foot fault on a second serve, giving Clijsters double match point.

Serena argued briefly, went back to the service line then directed a venomous rant at the offending lineswoman including a threat to "shove this ball down your throat."

The chair umpire assessed a point penalty for the outburst -- giving Clijsters the match.

2011: final vs Stosur

In the 2011 US Open final, chair umpire Eva Asderaki warned Williams for hindering opponent Stosur for shouting "come on" before the Australian had reached the ball.

An angry Williams -- who confused Asderaki with the umpire who was in the chair for the 2009 Clijsters match -- verbally attacked her during the changeover.

"If you ever see me walking down the hall, look the other way," she said.

"Because you're out of control. You're out of control. Totally out of control. You're a hater and you're just ... unattractive inside. Who would do such a thing? And I never complain. Wow. What a loser. You give a code violation because I expressed who I am? We're in America last I checked."

2018: final vs Osaka

Battling to get back in a match against a 20-year-old opponent playing in her first Grand Slam final, Williams was incensed to be warned for receiving coaching from her box.

A relatively calm conversation on a changeover seemed to settle things down, but Williams was further infuriated when she was docked a point for a second violation after smashing her racquet in frustration at dropping serve, calling chair umpire Carlos Ramos a "thief".

Broken again to trail 4-3, Williams continued to berate umpire Ramos. "You will never, ever, ever be on another court of mine," she fumed. "You are the liar," prompting Ramos to issue another violation and dock her a game under the ascending scale of punishments for repeated code violations and putting Osaka on the brink of victory.