Video: Controversy erupts at the Australian Open as American tennis player CoCo Vandeweghe mouths profanities at opponent

American tennis star CoCo Vandeweghe had a terrific start to the year as she entered the Australian Open boasting a career-high ranking of nine.

However, it looks like her good fortune has come to an end as she crashed out at the very first hurdle of the year’s first Grand Slam on Monday, losing to Hungarian Timea Babos 7-6 (7-4), 6-2 at the Hisense Arena.

The low point, though, came when the combustible American lost her temper and mouthed profanities at her opponent. It was towards the end of the second set that she appeared to have cursed the 51-ranked Babos.

In this video, it can be clearly seen that Vandeweghe is shouting out, “F*** you, you f***ing b****,” at her opponent and throwing her racquet in disgust.

Here is how Twitter reacted to the incident:

Of course, the chair umpire noticed it and docked a point.

After the match, Vandeweghe told the media that she wasn’t too happy with Babos getting “in her face”. However, the Hungarian, on her part, denied riling Vandeweghe up.

"She always does that (loses her temper)," Babos said, “A couple of racquets are broken every match, this time it was I believe a time violation, but I'm not sure.”

"The second one, I believe, was an insult against me. If the umpire heard it then it must have been this," she added.

It was the second time that Vandeweghe was given a code violation today. Earlier, at the end of the first set, she had refused to restart play until a ball-kid delivered her bananas. The umpire had docked a point for time wasting.

Later on, the 26-year-old American took to Twitter to express gratitude to her fans who came to watch the match.