Top seed and defending champion Roberto Bautista-Agut is out of the ASB Classic.
The Spaniard has withdrawn on Wednesday morning due to a stomach virus.
He was due to play his second round match with Jiri Vesely in the second match of the tournament.
New Zealander Rubin Statham will take his place in draw, as the `lucky loser' from qualifying.
It's not exactly a hammer blow for the event - as the world No14 was one of the lowest profile champions in recent years - but it's always unfortunate when the most recent winner is unable to defend his crown.