The deadline for tenders closed in mid-June and the union said there was strong interest from 16 parties before eight confirmed tenders were received.
The Saxbys Rd land in Deanwell is zoned as a recreational reserve but is proposed to be rezoned as residential in the draft district plan, which would make it suitable for a retirement village or about 80 medium-sized residential sections.
The city council requires the new buyer to retain some of the land into a public reserve and to protect the gullies around the park.
Part of the condition of the sale was that the Hamilton Rugby Union could keep using the park for junior rugby until August next year while the union worked with the council to identify alternative council-owned parkland to hold junior rugby games.
Hamilton Rugby Union chairman Peter Way said it was disappointing the council hadn't been willing to negotiate with the union to buy the park because it had good drainage, changing rooms and off-street parking, which many of the other parks lacked.
Mr Way said the union still had no new place for its 10 active clubs to play junior rugby long-term despite his warning the council since 2001 it would have to sell the park at some point.
The settlement date is early next year, when the proceeds would be transferred to the trust to administer. Nikki Preston