Handre Pollard scored 20 points with his boot as the Bulls tamed the Lions, while the Sharks tasted defeat for the first time this season.
Handre Pollard was instrumental as the Bulls eased to a 30-12 Super Rugby victory over the Lions at Ellis Park on Saturday, while the Stormers edged out the Sharks 16-11.
Duane Vermeulen and Warrick Gelant scored tries for the Bulls, but it was Pollard's kicking precision which proved decisive.
The 24-year-old plundered 20 points with his boot to ensure that Carlu Sadie and Dylan Smith's tries for the hosts, who have been runners-up in the past three Super Rugby finals, proved futile.
"It was a great team effort," said Pollard.
"I did not expect to win by such a wide margin given the Lions' record against us [the Lions have won their last four meetings].
"Everyone contributed and I want to give special praise to Eli Snyman [who replaced injured captain Lood de Jager]. He had big shoes to fill and lasted the full 80 minutes."
At Kings Park in Durban, meanwhile, the Stormers did just enough to inflict a first defeat of the season on the Sharks.
The Stormers got their reward for a bright start when full-back Damian Willemse intercepted to score the only try of the first half.
Sarel Petrus Marais added two penalties to extend the Stormers' lead, but Lukhanyo Am set up a tense finale with a try for the Sharks.
A second penalty from Robert Du Preez reduced the Stormers' lead to 13-11, but another Marais penalty ensured maximum points for the visitors.