Sharks fly-half Curwin Bosch kicked a penalty 150 seconds into additional time to snatch a 34-33 victory over Griquas Friday in a South African Super Rugby Unlocked thriller.
Bottom team Griquas twice led by 13 points during the second half at their Kimberley base and took a two-point lead on 80 minutes when fly-half Tinus de Beer slotted a penalty.
But the hosts then conceded a penalty and twice-capped Springbok Bosch made no mistake from 44 metres to keep alive a slim chance of winning the single-round competition.
No spectators were permitted at Griqua Park stadium in the northern Cape capital because of the coronavirus pandemic.
The Durban outfit trail leaders Bulls by two points and have home advantage over Stormers next Saturday in the final round.
However, Bulls appear to have an easier final fixture, at home to Pumas, and a bonus-point victory will assure the Pretoria franchise of a first domestic title since winning the 2009 Currie Cup.
"We were not good enough tonight," admitted Jeremy Ward, deputising as Sharks captain for injured fellow centre Lukhanyo Am.
"Our work at the breakdowns was disappointing and we conceded far too many penalties. It was just as well Curwin was in such good form with his goal-kicking."
Griquas scrum-half and skipper Zak Burger was not downbeat despite a fifth consecutive loss and only three points from a possible 25.
"Everyone played with pride and it was really unfortunate that we lost after taking the lead in the final minute of regular time," he said after the narrowest winning margin so far in the competition.
Bosch moved one point ahead of veteran Bulls fly-half Morne Steyn in the race to finish leading points scorer after amassing 14 from four conversions and two penalties.
Sharks' tries came from scrum-half Sanele Nohamba, substitute full-back Manie Libbok, Ward and substitute loose forward Dylan Richardson.
Man-of-the-match De Beer, a late pre-match inclusion after George Whitehead broke a hand, did not miss a kick at goal in compiling 18 points from three conversions and four penalties.
Griquas' try scorers in a match where they led 9-7 at half-time were winger Ederies Arendse and Eduan Keyter and lock Gideon van der Merwe.
On Saturday, Stormers host Cheetahs in Cape Town while three Pumas tested positive for coronavirus, leading to the postponement of their match against Lions scheduled for Johannesburg.