Keiran Van de Goot outpaced the Villagers defence in the 25th minute and made it 2-0, and United took that lead into the break.
The second half was a deadlock until Lawrie Scott scored late in the game to ensure the win for United.
At Crown Park, Taupo underlined their domination of the league with a 3-1 win over Waikato Unicol.
Byron Thessman gave Taupo a 1-0 lead at the break and Alan Lamb assured Taupo of retaining the Challenge Shield with a second half double.
Old Blues' fate is out of their control after a 3-1 loss to Otumoetai. If Tauranga Boys' College can win their last two games, Old Blues will be the second team relegated.
"Consistency was missing again. We played well last week but didn't perform today," disappointed Blues coach Andy Legget said after the game.
It was a scoreless first half but Matt Collins put Otumoetai ahead before Reuben Wood equalised for Old Blues.
The key moment in the game came when Old Blues failed to convert a penalty.
Otumoetai's Matt Collins did not waste his chance from the spot, and with Old Blues pushing forward in search of the equaliser Daniel Miller scored to confirm the win.