Nelson Park won three times earlier this year before he was given a break.
"He went out for two months and he's put on 30 kilos, which he's kept on," Hapeta said.
"He trialled up well at Avondale and I would be very surprised if he didn't go a good race."
Nelson Park will be ridden by Mark Du Plessis, who has won on the gelding and who partnered him at the trials last month.
"We'll take it a race at a time and Mark knows the horse so he'll tell us whether we go straight to a mile next time or give him another 1400," Hapeta said.
"I would like to get him up to 2000m at some stage - he's got a good cruising speed and I'm sure he'll make it in open class."
- NZ Racing Desk