Heaslip made his Lions debut in the 26-21 defeat at the ABSA Stadium last weekend and says the experience hasn't dented any of the pride or confidence of the tourists. They know exactly what they need to do at Loftus Versfeld on Saturday to square the series.
"We showed them what we are capable of with the ball in our hands in the second half. We have to get control of the game as we did in that second period," said Heaslip.
"We ended the game stronger than them and we need to keep the ball in play. It seemed to be out of play for long periods last weekend and that made it hard for us to get into the game.
"But when we did we proved we can cause them plenty of hassle. We are going to attack them from everywhere on the pitch this weekend and we need to stop them physically."
The Lions have been written off by the locals for two reasons this weekend. Firstly, they are returning to play at altitude and, secondly, because they are playing at the home of the Super 14 champions, the Bulls.
But neither is causing Heaslip or his team-mates too many concerns. They spent almost two weeks at altitude at the start of the tour and proved they were much fitter than the Boks with their second-half come back last weekend.
"It was the same kind of intensity last weekend as I've experienced in the Heineken Cup semi-finals and final this season and the Grand Slam game. In the end, it just comes down to 15 against 15 on the pitch," he added.
"It will be nice to play in an intimidating atmosphere, but that's what you get used to as a professional player."