The Stormers struggled through another poor second-half performance to beat New South Wales Waratahs 19-13 and move atop the Super 15 Saturday. Tries by Joe Pietersen and Tiaan Liebenberg helped open a 16-3 halftime lead at Newlands for the Stormers, who dominated the first half but then slipped away in the second. The Waratahs have lost four in a row. In Bloemfontein, South Africa, Meyer Bosman scored a late try against his former team to finally put the Sharks out of range of the Cheetahs and seal a 34-20 win in an all-South African tussle. Replacement back Bosman went over for the Sharks' fourth try with six minutes left at the Cheetahs' Free State Stadium. It ensured the Durban-based team continued its late-season surge and stayed on track for the playoffs. The bonus-point win lifts the Sharks into sixth in the overall standings. It was their fourth victory in five games. Earlier in the day in Christchurch, Hooker Corey Flynn scored two of nine tries for the Canterbury Crusaders who crushed the Auckland Blues 59-12, posting their largest-ever win over their New Zealand rivals. The Crusaders atoned for last week's shock loss to the Melbourne Rebels, which jolted their playoffs hopes, taking only 36 minutes to claim a four-try bonus point that kept them in fifth place after the tournament's 13th round. In Brisbane, Australia flyhalf Quade Cooper made his first match appearance in seven months to set up Queensland's first try and 18-year-old wing Chris Feauai-Sautia later added a try within minutes of making his Super 15 debut as the Reds beat the Lions 34-20. Cooper was substituted at halftime of Saturday's match but did not appear to have any further fitness concerns. In New Zealand, Otago lock Jarrad Hoeata had one try disallowed but immediately scored another to lead the Highlanders to a 16-11 win over the Bulls, ending the South African team's brief reign atop the table.