Wellington kept in touch with Championship leaders Hawke's Bay after they battled past Premiership strugglers Waikato 21-14 in Hamilton on Sunday.
In a match played in ideal rugby conditions, tries from second-row Jeremy Thrush and hooker Leni Apisai saw the Lions to a much-needed triumph.
Chauncy Edwardson was Waikato's lone try-scorer and despite Damian McKenzie's three penalties, Jason Woodward kicked 11 points in reply.
Waikato are second bottom in the Premiership standings, just two points ahead of bottom side Manawatu as they battle to avoid relegation to the Championship
Pens: McKenzie 3
Tries: Thrush, Apisai
Pens: Woodward 3
Waikato: 15 Shaun Stevenson, 14 Regan Ware, 13 Anton Lienert-Brown, 12 Jordan Payne, 11 Dylan Collier, 10 Damian McKenzie, 9 Brad Weber, 8 Adam Burn, 7 Mitchell Jacobson, 6 James Tucker, 5 Peni Iowane, 4 Jacob Skeen, 3 Josh Hohneck, 2 Epalahame Faiva, 1 Atunaisa Moli.
Replacements: 16 Tyrone Te Ruruku, 17 Tau Koloamatangi, 18 Joe Walsh, 19 Josh Tyrell, 20 Zane Kapeli, 21 Harrison Levien, 22 Wharenui Hawera, 23 Chauncy Edwardson.
Wellington: 15 Jason Woodward, 14 Joe Hill, 13 Matt Proctor, 12 Marvin Karawana, 11 Wes Goosen, 10 Jonny Bentley, 9 Tomasi Palu, 8 Ardie Savea, 7 Greg Foe, 6 Vaea Fifita, 5 Hoani Matenga, 4 Jeremy Thrush, 3 Jeff Toomaga-Allen, 2 Leni Apisai, 1 Reg Goodes.
Replacements: 16 James O'Reilly, 17 Vincent Sakaria, 18 Whetu Henry, 19 James Blackwell, 20 Adam Hill, 21 Frae Wilson, 22 Jackson Garden-Bachop, 23 Tomasi Alosio.
Referee: Brendon Pickerill