The genesis of the tennis grunt is disputed. Some say the grunt was invented in Nick Bollettieri's tennis laboratory where, convinced a noisy expulsion would help a player hit the ball harder, the famed coach played soundtracks from pornographic movies near the test tubes in which his ''Deci-belles'' were incubating.

Others are adamant the shriek was secretly encouraged by the WTA Tour marketing department, which hoped to keep spectators awake during early-round matches.

Regardless of where the blame lies, long after Monica Seles prompted Peter Ustinov's famous aside - ''I would hate to be in the next room on her wedding night'' - and English tabloid hacks scurried to Wimbledon with their hand-made ''gruntometers'', the grunt remains one of the game's enduring yelling points.

On Monday night, as Maria Sharapova gave birth to a fourth-round victory over Sabine Lisicki, seldom has Sir Norman Mute's patented sound-killing device provided such sweet relief. So it was with some trepidation, and a pair of industrial ear muffs, that we headed to Rod Laver Arena to hear Victoria Azarenka, the new First Lady of Loud.

Azarenka's barnyard impressions had incited the usually generous Melbourne Park crowd to mimic her grunts during a match against Casey Dellacqua. That prompted some to suggest local fans had done what the WTA and ITF will not - take the grunting bovines by the horns. Although, having inflicted the inane caterwauling of the Fanatics upon the world, Australians are not well placed to condemn noisy intrusions into the reverential silence of centre court.

Yesterday, as Azarenka eventually shouted down the mercifully muffled Agnieszka Radwanska 6-7, 6-0, 6-2, a few grunting wags gave the Belarusian grief. However, it might have been argued the grunting was a welcome distraction from the match - two hours of cavewoman tennis during which the odd drop shot or moon-ball were the only diversions from the monotonous backcourt slugging and, at the service line, both players sometimes made Anna Kournikova seem like Pete Sampras.

One benefit of the grunt is that it makes the grunter seem like she is giving her all. Although Azarenka's emissions stray well beyond ''woman busting a gut'' into the realms of ''woman having her nipples pierced with a blunt needle''. It is difficult to describe, let alone spell, the noise Azarenka makes as she swipes the ball. However, when the umpire called for ''new balls'', it might have been in the mistaken belief she had heard a choir of castrated schoolboys.

Some allege grunters are cheats because their noise is intended to disguise the sound of the ball coming from the racquet strings or to distract their opponents. This, they argue, is why the grunts grow louder under pressure. But, even during an abject first set tie-breaker in which she failed to win a point, her screams were admirably consistent. Admittedly, she would need to pull a megaphone out to pump up the volume.

''It's the way I am, the way I play, the way I used to play,'' said the 22-year-old Azarenka, who claims she was a ''weak child'' and grunting helped her hit the ball harder. As for talk the WTA will investigate grunting? ''I think it's kind of silly.''

Some might say the same of Azarenka's emissions. However, the manner in which she overcame an early deficit and ploughed her way into a second grand slam semi-final in searing heat was impressive. That work ethic comes from a grandmother who, age 71, had to be forced to sign a document relinquishing her job as a kindergarten teacher. The bloodlines suggest granny would have had no problem being heard above a room of four-year-olds.

Despite the taunts, Azarenka told the crowd, ''I love youse guys.''

However, in a semi-final against local favourite ''Aussie'' Kim Clijsters, the No.3 seed will not have many more friends than she supposedly has among the courtesy drivers and locker-room attendants. That unpopularity is, apparently, the consequence of a brusque demeanour, not a grunt that can take the skin off the custard in the players' cafeteria from 15 courts away.

The semi-final is on Australia Day when, traditionally, tennis patrons complain about noisy intrusions. Now it might be those outside Melbourne Park unable to hear the fireworks or heavy metal bands at the nearby Myer Music Bowl above Azarenka's shrieks who are enraged.

The Deci-Belles Take It For Grunted As Emissions Hit All-Time High