Tennis: Del Potro's ASB Classic exit part of ATP Tour trend

Juan Martin Del Potro's injury withdrawal from the ASB Classic is unfortunate, but hardly unexpected.

The 2009 US Open champion confirmed on Saturday morning he wouldn't be making the trip down under, with an ongoing wrist injury that will keep him out of the Australian Open as well.

It's become par for the course over the last few years for the Auckland men's tournament, with the likes of Gael Monfils, John Isner, Tommy Robredo and David Ferrer being announced in a wave of publicity, only to pull out a few months later.

The merit of their reasons have varied. Isner gave the impression he just couldn't be bothered in 2015 (and turned up this year as a make up), Monfils succumbed to one of his mysterious phantom injuries (citing personal reasons) while Robredo hurt himself in training two days before his first match.

In 2015 Ferrer had credit in the bank with the ASB Classic - given his loyalty over the years - so fans were sympathetic when the Spaniard decided his exertions in the Middle East the week before meant he needed to rest before the Australian Open.

The four time champion also showed his class by flying across the Tasman to shake a few hands, fulfil sponsor commitments and complete a training session.

Del Potro has been plagued by a wrist injury over the last few years, one that took him off the court for long periods. His was a heart warming story this year - especially at the Rio Olympics - but it was inevitable that the injury might re-occur again.

It's also part of a wider trend among the ATP tour. Del Potro's situation is genuine, but over the last five years or so the top players have become indifferent to playing tournaments in the first two weeks of the year.

Around 80 per cent of the world's top 20 won't play in a tour event in early January, instead preferring training blocs and meaningless (but cash rich) exhibitions before the Australian Open.

There is also the fatigue factor, as the calendar gets more and more jammed with events.

The absence of Del Potro robs the men's week of genuine star power. The Argentine is a marquee name, and one of only three men outside the trio of Roger Federer, Rafa Nadal and Novak Djokovic to win a grand slam since 2009.

But let's keep it in perspective. Barring further withdrawals, Auckland tennis will still see Ferrer, Isner, Jack Sock, defending champion Roberto Bautista-Agut and Feliciano Lopez.

There is also unpredictable Cypriot Marcos Bagdahtis and surprise 2015 winner JIri Vesely, who came through qualifying to take the title.

The only disappointing aspect is the timing of the Del Potro announcement. Tournament organisers strongly refuted reports on Wednesday that the 27-year-old was in doubt, so it is easy to be cynical about the release of the bad news on Christmas Eve morning, to minimise the publicity.