Sharks director of rugby Gary Gold praised his team's defensive effort that helped secure an 18-13 win over the Stormers at Newlands at the weekend, but admitted that they need to improve.The Sharks are the only unbeaten South African team in the competition after three rounds. They head the South African Conference and are also top of the Africa 2 Conference on 13 points.The Sharks made 164 tackles to the Stormers' 101, but only had 42% possession and 43% territory."Everybody played his part. We realised that, against such a good Stormers team, we had to work hard at set pieces to get parity at least," Gold said."We did substantially more defending and showed a lot of character, which makes me very proud. But it's fair to say we are not going to be able to go through a season like that."We are going to have to look after the ball a lot better."One of the secrets of their win was Marcell Coetzee's superb work from open-side flank. He pilfered three balls to halt the Stormers momentum at crucial times. His workrate and decision-making were superb throughout the match and, in a game of fine margins, his contribution was pivotal."Marcell is immense and what is getting better, as he becomes more experienced, is his decision-making," Gold said.The Sharks have a short turnaround this week,L before taking on the Bulls at Loftus on Friday night. Considering the physical battle against the Stormers and one less day to prepare, Gold will consider rotating several players this week...