Quentin Johnson, Robert Clarkson, Hamish Gold and Carlssen van Rooyen are Otago's only competitors this week for the international tournament, held in Queenstown for the third time.
New Zealand dominates over a third of the talent pool with 50 competitors out of a hefty 148.
The highest-ranked New Zealander competing is 12-time champion Anthony Ker, from Wellington, currently top in the country.
Yesterday in the second round of the tournament, all four Otago representatives were still in the running, chief organiser Paul Spiller said.
Mr Spiller said there were several "world-class" players at the tournament including world No 40 and tournament top seed Li Chao, of China, Commonwealth champion Gawain Jones, of England, and six-time Indian champion Surya Ganguly.
Zhao Xue, of China, is seventh-ranked female in the world.
He said matches on average take four to five hours. He predicted events would finish about 9pm most evenings.
Players are competing for up to $30,000 in cash prizes.
Among the field are 11 grandmasters, four women grandmasters, 11 international masters as well as four female international masters.
The classic incorporates the 119th New Zealand Chess Championships, with matches at the Millennium Hotel this week from 3pm daily.
