Two brilliant tries in the last quarter by David Smith enabled the Force to beat the Highlanders 21-14 in their Super Rugby match at Carisbrook on Friday.
The Force, who trailed 3-14 at half-time, dominated the second spell as the out-of-sorts Highlanders wilted under the barrage as they conceded 18 unanswered points.
It was their second consecutive home loss and their chances of making the playoffs are now over.
Smith, James Stannard, David Pocock, Matt Hodgson and Nathan Sharpe were at the forefront of a rousing Force display.
The Highlanders were making their farewell to Carisbrook and were in eighth place on 44 points. The Force were 12th on 28.
The Highlanders' playoff chances were in severe jeopardy after their 22-26 loss to the bottom-placed Lions last weekend while the Force had taken the Hurricanes to the wire before losing 28-34.
The Force had won the last three matches against the Highlanders but there was a late change in their team, Cameron Shepherd withdrawing through injury. Mitch Inman came into the side at centre and Patrick Dellit moved to fullback.
The Highlanders fielded in their new strip of lime green jerseys and blue shorts before a disappointing crowd of about 6000 on a fine but cold night.
The Force scored first after 11 minutes when, after working their way downfield from four consecutive penalties, James Stannard kicked a sitter from in front.
But Sopoaga tied the scores with an equally easy penalty three minutes later and then put the Highlanders in front with a much more difficult kick.
The Highlanders scored the first try after 23minutes when Jimmy Cowan found touch 60 metres downfield, the Force bungled the lineout and Ben Smith collected a miss pass and crashed over in a tackle to make it 11-3.
Stannard was sin-binned after 26 minutes for an early tackle on Siale Piutau and Sopoaga's third penalty extended the Highlanders' lead to 14-3.
They almost scored their second try after 32 minutes but Adam Thomson, in his 50th game for the franchise, was forced into touch in goal.
The Highlanders went into the break with an 11-point lead but it had been a mixed bag. The Force had an edge in territory and possession and the Highlanders had made more handling errors (7-3) and missed more tackles (11-6). The Highlanders had also blown two gilt-edged try-scoring chances.
Sopoaga had a chance to put the Highlanders 17-3 in front early in the second but hooked his kick, from 40 metres and in front, wide of the posts. Nasi Manu was over two minutes later for what seemed a fair try after a fine break by Piutau but the referee controversially ruled the ball had gone forward from the winger when it had come off the head of Force flanker Matt Hodgson.
The Force repelled wave after wave of attacks from the Highlanders in the first 15 minutes of the second spell but kept their line intact with stoic defence and the Highlanders' errors.
The Force hammered away and finally scored their first try 16 minutes from the end, left wing David Smith scoring in the right corner after Pocock had been held just short. Stannard converted from the sideline and, at 14-10, it was game on.
The Highlanders were just holding on and the Force had the momentum going into the last 10 minutes.
Stannard kicked a handy penalty with nine