Playing its most impressive football of the season, Otago dominated the first half against a Manawatu side that passed the ball confidently but lacked penetration.
Manawatu keeper Chris Marsh did well to save a snappy overhead volley as Aaron Burgess got on the end of a left-wing cross from Barry Gardiner.
Then Burgess sliced through a gap and with keeper Marsh advancing flicked the ball past him, but just wide of the post.
But the big keeper stood no chance when Robbie Deeley strode on to a weak clearance and hammered in a 30m drive to put Otago ahead after 29min.
For the visitors, Leo Shin was a handful, and went closest with a couple of shots on the turn that Liam Little saved.
In the second half, Manawatu lengthened its passing game, and from a wide attacking position Jason Hayne became more effective, slinging over crosses that stretched the Otago defence.
A series of corners had keeper Little punching the ball clear, before he was injured in a goalmouth melee, and eventually had to be replaced by Callum Flaws.
Cory Chettleburgh drilled in the equaliser after 72min, and Hayne found space to shoot Manawatu into the lead only three minutes later.
However, Otago continued to push forward with its three-man attack, and won a couple of right wing corners from which Falvey headed the equaliser, albeit after referee Jamie Cross consulted with assistant Ken Nare as to whether the ball had crossed the goal line. At two goals apiece, most teams would have gone conservative, but the crowd at Sunnyvale was treated to continued attacking football with gaps appearing all over the field.
It was a driven diagonal cross that eventually beat Otago's defence when, with minutes to go, Hayne ghosted in at the far post to head the winner past keeper Flaws.
Was the party over? No chance. Otago earned several more long throws and corners that threatened to earn a share of the points, but Manawatu survived.
Visiting coach Bob Sova said, "It really was quite dramatic. Must have been good value for the spectators. I was pleased with our passing game and [Raf] De Gregorio's control in midfield."
For Otago's coaching trio, the mantra of "Do not give the ball away" was again repeated, and assistant coach Malcolm Fleming felt that Otago should have had at least a share of the points.
