Kim Sears
Kim Sears is seen swearing after Murray loses the first set in the Australian open.AFP / Getty Images

Andy Murray has defended his fiancée Kim Sears, after she was caught on camera launching a tirade of abuse at the Wimbledon champion's opponent.

Tensions were heightened as the British number one battled it out on the court with Tomas Berdych to win the Australian Open semi-final. When Murray broke back in a tense first set Sears directed her outburst towards the Czech player's team.

The blonde beauty appeared to direct a string of expletives towards Berdych seemingly mouthing the words "F*****g have that, you Czech flash f***", and "Take that, you flash f**k."

Spectators took time to settle down after seeing a replay on the video screen of Sears reacting to the previous point and the incident sent Twitter into meltdown as social media users reacted with amusement and shock at the unexpected outburst.

Reacting to the incident after, Murray who proposed to his girlfriend of nine years last year, said: "In the heat of the moment, you can say stuff that you regret."

Murray and Berydch too appeared to have a heated verbal exchange during the hard-fought match. The Scot was annoyed by Berdych's complaints about the balls, while his opponent appeared to pass a comment during the changeover.

"It was only in the first set there was tension, like right at the beginning of the match," added Murray.

"It wasn't like there was loads going on there. Obviously at the end of the set, when he said something, that was really the last thing in the entire match where there was any tension. It was fine after that."

Explaining his version of the incident Berdych denied any wrong doing. "I said to myself: 'Well done, Tomas'," he explained. "That's it. That's what I said. I think I'm allowed to do that when I win a set."

Murray attributed the tensions to the focus on his former coach, Dani Vallverdu, who is now working with Berdych.

"When there's a lot of tension surrounding something, which you created, it's completely normal that the whole first set everyone was tight," Murray explained.

"Even Tomas, who very rarely says anything on the court... there was tension there for him as well," he added.

The former Wimbledon champion lost the first set in a tie-break, but fought back to win his eighth Grand Slam final.

After his win, Murray took the opportunity to show his support for his coach, Amelie Mauresmo, saying: "I'm just very happy for her that I won the match. "I got asked all the time about my ex-coach working with Tomas and no one was interested in anything I was doing with Amelie or the way I was playing or anything.

"A lot of people were also criticising her at the end of last year, like the way I was playing was her fault, when I'd spent two weeks training with her up to the end of the year, until the training block. There was very little time to spend with each other. There's no reason for her to be criticised for anything."

Murray has lost in three previous Australian Open finals, in 2010, 2011 and 2013. He now joins the likes of Andre Agassi and his former coach Ivan Lendl as a four-time Australian Open finalist.

"To be in the final four times here, because I'm surrounded by guys like Roger, Novak and Rafa, doesn't look like much, but that doesn't happen that often," he said. "I'm very proud of that."

Murray will face Serb Novak Djokovic or Switzerland's Stan Wawrinka on Sunday. (1 February)