Tasman were left scoreless by Southland in their Air New Zealand Cup clash on Saturday, after the home side ran in seven tries to record a 41-0 win rout at Invercargill's Rugby Park.
Southland returned to form in emphatic fashion, scoring six unanswered tries in the second half after leading 7-0 at half-time.
Stags full-back Glen Horton crossed for a hat-trick, while Jimmy Cowan, Jason Kawau, John Hardie, and Jason Rutledge also dotted down for Southland.
The win moves Southland up to third on the competition ladder, while Tasman has dropped to seventh - leaving their play-off hopes in the balance.
It took nearly 20 minutes for the southerners to get points on the board, when returning All Blacks scrum-half Cowan finally broke through Tasman's defence after captain Jamie Mackintosh's initial assault on the line was repulsed.
Southland pivot Robbie Robinson converted, but Southland couldn't add to the score before the half-time whistle.
It was a different story in the second half, as Southland showed their intentions within the first two minutes with Horton crossing for the first of his three tries.
The second followed soon after, as the Southland back-line started to run riot, given the perfect platform to perform on thanks to a sterling effort from their relentless forwards.
Centre Kawau and loose forward Hardie added to the score in quick succession before Horton brought up his hat-trick with just over ten minutes to go.
Fittingly, the last try of the match went to hard-working hooker Rutledge, who burrowed over in the corner in the last minute of play.
Tries: Horton 3, J Cowan, Kawau, Hardie, Rutledge
Cons: Robinson 3
Southland: 15 Glen Horton, 14 Matt Saunders, 13 Kenny Lynn, 12 Jason Kawau, 11 Pehi Te Whare, 10 Robbie Robinson, 9 Jimmy Cowan, 8 Hua Tamariki, 7 Tim Boys, 6 John Hardie, 5 Dave Gannon, 4 Josh Bekhuis, 3 Chris King, 2 Jason Rutledge, 1 Jamie Mackintosh,
Replacements: 16 David Hall, 17 Fai Mika, 18 Joe Tuineau, 19 Noa Soqeta, 20 Scott Cowan, 21 Seminar Manu, 22 James Wilson,
Tasman: 15 Robbie Malneek, 14 Blair Cook, 13 Kade Poki, 12 Andrew Goodman, 11 Afeleki Pelenise, 10 Kahn Fotuali'i, 9 Shaun Begg, 8 Mark Bright, 7 Jonathan Poff, 6 Glen Gregory, 5 Joe Wheeler, 4 Alex Ainley, 3 Tristan Moran, 2 Quentin MacDonald, 1 Sakaria Taulafo.
Replacements: 16 Daniel Perrin, 17 Hamish Cochrane, 18 Daniel Hyatt, 19 Zane Winslade, 20 Ammon Matuauto, 21 Matty James, 22 James Kamana,
Referee: Mike Fraser