Defending champions Northern Bulls and the Coastal Sharks will face a potential winner-takes-all South African derby next week to reach the top-six play-offs of this year\'s Super 15 tournament. The Pretoria-based Bulls kept alive their hopes of winning a fourth southern hemisphere championship title in five seasons with a 19-16 win over the Western Stormers in Cape Town on Saturday to nudge ahead of the Sharks into fifth spot. The Sharks snatched a dramatic 30-30 draw with the Golden Lions in another South African derby to slip to sixth. Both the Bulls and Sharks face a likely make-or-break showdown in Pretoria next Saturday if the New South Wales Waratahs win their Australian derby against the ACT Brumbies a few hours earlier in Sydney. The Waratahs picked up a bonus point in their 33-7 home win over the Otago Highlanders to lie in seventh place, just one point behind the Bulls and Sharks in what is developing into an absorbing climax to the Super 15 regular season. Australia\'s Queensland Reds, Stormers and Canterbury Crusaders have clinched play-off spots with the Auckland Blues only needing one point from their final home game against the Highlanders to seal their place. The injury-hit Reds came from behind to beat Western Force 24-21 in Perth, while seven-time Super Rugby champions Canterbury went to the top of the New Zealand Conference with a 23-16 win over the Blues in Timaru. In the weekend\'s other matches, the Waikato Chiefs and Wellington Hurricanes played out the second draw of the weekend round in an 18-18 stalemate in Hamilton, while the Brumbies had a convincing 32-17 win over the Melbourne Rebels in Canberra. At sold-out Newlands, the Bulls had to withstand a late assault by the Stormers to take the points in a thrilling derby. The Stormers scored a 79th-minute try and forced the Bulls to defend for three minutes after the final hooter before their attack broke down near the Bulls line. Stormers stayed in second place in the table and will earn a home semi-final if they beat the Central Cheetahs in their final league match in Bloemfontein next weekend. \"Everything is still in our own hands,\" said Bulls captain and lock Victor Matfield. \"The Sharks are going to be very tough but we’ve still got a chance.\" In Johannesburg, the Sharks scored 21 unanswered points to snatch a draw against fellow the Lions. The two points lifted the Durban team to fifth after they trailed the Lions 30-9 until coach John Plumtree introduced several players, including French utility back Frederic Michalak for his first appearance of a second spell with the side. The Lions seeking to end a 763-day run without a home win, could not hold out the Sharks, who levelled after a precise Patrick Lambie grubber kick set up winger Lwazi Mvovo up to score. \"Now we face a colossal battle with the Bulls in Pretoria next weekend and we have got to get something out of that game,\" skipper John Smit said. A Tom Carter hat-trick of tries kept the Waratahs in the play-off hunt against the Highlanders in Sydney on Saturday. The Waratahs scored five tries with Wallaby fullback Kurtley Beale in irresistible form to end Otago\'s outside play-off hopes. In Perth, the Reds, outplayed for the much of the game and missing several injured players, stayed in touch through the brilliance of Quade Cooper and snatched victory in the dying seconds. In a massive boost to their hopes of securing a home semi-final, the Reds scored the winning try in the 79th minute through replacement Dom Shipperley. The Crusaders seized control of the New Zealand Conference when two tries by Zac Guildford cemented a hard-fought win over the Blues. It was sweet revenge for the itinerant Crusaders, left homeless by the devastating Christchurch earthquake in February, who were beaten by the Blues 22-24 in the opening round.