Josh Robertson-Weepu converted from the chalk to give the home side a 13-6 lead.
But not for the first time this season Te Puke lost momentum and let the opposition back into the game with their own unforced errors.
If there had been a heart monitor on coach Craig Jeffries it might have gone off the scale as his team conceded needless penalties that Matt Golding converted into points.
At 13-12 the match was in the balance and Mount had the better attacking opportunities in the second half. But that famous Pirates mentality shone through as they defended their line well and then won the match with an excellent team try.
The hard-working Te Puke pack turned over the ball 30m out and two quick switches of play and accurate passes saw replacement winger Conor Hirini over in the corner.
Fullback Robertson-Weepu, who continues to impress with his goalkicking and strong running, added the conversion for a final 20-12 scoreline.
Jeffries was full of praise for his players, who jubilantly celebrated with the Jordan Cup after the game.
"We are absolutely delighted and happy as hell to get that cup back and get the competition points that jump us to the top of the leader board," Jeffries said.
"When we won it [Jordon Cup] earlier in the season we made a pact that we want to keep it for the rest of the season. We didn't do that so we have had a bit of a focus on that this week. Our manager [Ross Flexman] went out and got the history of it and it goes back a hell of a long way.
"The boys are really proud of it."
Jeffries said defence was undoubtedly the key to the win.
"We have been good on D all year. The boys are really committing and communicating well. They are a good side so we knew they had threats all over the park so we just had to be hungry all game. It was a real good effort."
The semifinalists will be decided after the final whistle next Saturday.
Te Puke and Rangataua are on 21 points, with Mount Maunganui (20), Rotoiti (18), Te Puna (16) and Greerton Marist (13) all in the mix.
