Pearce said that Rea, who plays his tennis at the University of Tennessee, had been considered but in the end it had been decided to go with the rankings in giving it to Nielsen.
At the Residentials, Rea beat Nielsen in the semifinals and went on to beat Alistair Hunt in the final. Although Rea has current form on his side, Pearce said the decision was simply based on remaining consistent and rewarding players on the ATP Tour.
In his past two Open appearances, Nielsen has gone out in straight sets in the opening round. He missed the 1999 Open but in 1998 won his first match before bowing out to Marcelo Rios.
At the end of last year, Willman was ranked 359 and Nielsen 457. Rea was not ranked but now seems certain to get a place in the singles qualifying draw as one of four wildcards which Pearce will almost certainly hand to local players.
Rea, James Shortall, Robbie Cheyne and Hunt should get their chance.
With no qualifying tournament for the doubles, it seems likely New Zealanders will figure in the allocation of three wildcards in that main draw.
Pearce is to talk pairings with New Zealand Davis Cup captain Glen Wilson.
Of reports that open second seed Goran Ivanisevic is struggling with a shoulder injury, Pearce said the Croatian had won his latest match at the ATP tournament in Doha and that he expected to see the Wimbledon champion here later this week.
Pearce confirmed the Open was close to a sellout, with even the worst day 95 per cent sold.
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