The Stormers strengthened their position atop the South African Super Rugby conference with a 27-17 victory over the Lions in Cape Town.
The win gave the Stormers 58 points, four behind overall leaders Waikato Chiefs and nine ahead of their nearest South African challengers.
They were made to work hard against a Lions team which went into the match having claimed just two victories in this year's competition.
The unfancied Lions trailed by three points with 10 minutes left before two tries in a six-minute spell ended their hopes.
Elsewhere, the ACT Brumbies rocked the Western Force with four first-half tries before clinging on for a 28-17 victory last night to move back ahead of the Queensland Reds in the race for the Australian conference title.
The Reds had pulled level with the Brumbies with a win in Melbourne on Friday but the Canberra-based side secured the all-important bonus point before halftime and held off a spirited Force fightback in the second period.
In the other all-South African match, the Bulls ran in six tries and were 40-nil up after an hour as they breezed past the Cheetahs 40-24.