Leading by 21 points with 30 minutes to go at the Free State Stadium, the Sharks had to withstand a late charge from the Cheetahs to win 29-22.
Tries from flank Lappies Labuschagne and new signing Johann Sadie, along with two conversions and a penalty from Johan Goosen narrowed the gap to just four points with twelve minutes on the clock.
Hero of the day, Patrick Lambie, put pay to Cheetahs fans dreams of an upset win, completing a memorable individual performance with a close-range penalty to round off matters.
Cheetahs were first to score with No 8 Philip van der Walt barging over after a line-out, but three Lambie penalties and the conversion of an opportunist Lwazi Mvovo try allowed Sharks to turn 16-5 ahead.
Man of the match Lambie, who contributed 19 points from five penalties and two conversions, did not miss a shot at goal and his tactical kicking was often superb, outplaying young pretender to the throne, Johan Goosen.
Marcell Coetzee dived over after a forward surge and Lambie converted and added a penalty to push Sharks to a 26-5 lead before a Cheetahs side struggling in the set pieces, eventually kicked into gear.
The Cheetahs face the Chiefs next Saturday in Hamilton, while the Sharks host the Stormers in a repeat of last year’s semi-final.
SHARKS: Lwazi Mvovo, Marcell Coetzee tries; Pat Lambie 2 con, 5 pens
CHEETAHS: Philip van der Walt, Lappies Labuschagne, Johann Sadie tries; Johan Goosen 2 con, 1pen
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