According to Mangan, Bradman, Lara, Tendulkar and Ponting all peaked at the said age. The batting average of even the greatest cricketers usually dips when they continue playing into their late 30s, with 29.875 years being the age when their averages hit a peak, a new study has suggested.

This information comes after former Australia skipper Ricky Ponting endured an unwelcome scrutiny following his fifth-ball duck in the Brisbane Test against South Africa, with some saying that his international career was close to being over.

In a thesis titled 'Ageing and Test Cricket Averages; A Statistical Note', professor John Mangan found the batting average of even the greatest batsmen usually dip if they continue to play into their late 30s, the Sydney Morning Herald reports.

According to the paper, based on a study of 12 current and former legendary run scorers, including Ponting, Michael Hussey, Sir Donald Bradman, Sachin Tendulkar and Brian Lara, Mangan found that their highest batting average was achieved at the average age of 29.875.

Mangan says that in Ponting's case, after a superb century against England in the 2006-07 series, he finished the Adelaide Oval Test with a batting average of 59.99, and was just shy of his 32nd birthday at the time. Since then he has played in 59 Tests and amassed 4107 runs at an average of 41.07.

The figures, compiled before his duck against the Proteas in the opening Test, are still respectable but show a steady decline which Mangan believes is likely to continue should he make good on his vow to bat on for another two Ashes series, the paper said.

However, Mangan says that Jacques Kallis bucks the trend. At a time when many of his 30-something colleagues are fading, the prolific Proteas all-rounder is not only defying 'Father Time' but possibly becoming even better at the age of 37.

"I can't imagine anybody except Kallis has got better at 35 or 36," he said.