The Bulls' nervous victory over a determined Sharks side was a dress rehearsal of what they could expect in the Super Rugby play-offs.
The Pretoria-based side nearly came unstuck against the visitors from Durban but the 20-19 victory at Loftus Versfeld launched them into the first place in the overall standings.
The Bulls are two points clear of the Chiefs at the top of the table and could consolidate their position with a victory over the Stormers in their final round-robin match in Cape Town next week.
Bulls captain Dewald Potgieter was visibly relieved and said his team had used their "get-out-of-jail card" against the Sharks.
"It was intense but I just want to take a step back and say hats off to our guys for keeping composure and showing some resilience," said Potgieter.
"The bounce of the ball and one or two calls went against us but they really stood up and this was a big win for us."
The Bulls left it late for the slender victory and also got the rub of the green as Sharks full-back Riaan Viljoen missed with his penalty attempt with two minutes left on the clock.
The scoreline was also coincidentally the same as the two sides' 2007 Super Rugby Final when the Bulls claimed the title in the dying moments of that match.
The match developed into one of the best derbies of the season as both team's dished up thrilling performances.
The Bulls trailed the visitors 19-13 until replacement scrum-half Jano Vermaak scored the decider with fly-half Morne Steyn converting for the lead with eight minutes to spare.
Bulls coach Frans Ludeke commended his charges for grinding out the victory.
"We had a lot of opportunities but we didn't finish them off in the first half and we just kept going," said Ludeke.
"Credit to the leaders on the field and for the way the players just stuck together and pulled it off in the end.
"That is the kind of character you need in this final phase."
The home side were severely penalised by referee Jason Jaftha particularly at the breakdowns, while the Sharks went relatively unpunished in this facet of the game.
Potgieter said would determine what they did wrong during their review of the match and remedy the problem as soon as possible.
"A lot it came down to the breakdown and how it was refereed tonight and we needed to make an adjustments," he said.
"The breakdown is one of the biggest parts of the game these days and maybe we sometimes went in there with reckless abandon.
"It is a good learning school for the guys to see that sometimes the interpretation is going against you and then you need to adjust from that."
He said the team adjusted in this area of play by committing less players in the breakdown with more staying on their feet and find other ways of forcing the turnovers.