Cape Town - Werner Kok and Kwagga Smith again proved their worth for the Springbok Sevens team at the past weekend's Nelson Mandela Bay Sevens.The Blitzbokke defeated New Zealand 26-17 in a pulsating Cup final on Sunday night, a week after they claimed the Dubai Sevens title.Speedster Seabelo Senatla may have stolen the show with his eight tries in Port Elizabeth, but Kok and Smith's performances should not be undervalued.Kok and Smith also bagged four tries apiece at the event, but their defensive efforts should be lauded.The improvement in team defences has been evident on the Sevens World Series circuit this season. It has also resulted in teams starting to employ tactical kicking on a more regular basis, with kicking from deep now a regular occurrence. New Zealand's narrow 5-0 victory over England in the pool stages was a clear example of how defence has become an integral part of the sevens game.Kok currently leads the way as the best defender on the circuit, boasting 58 tackles in the first three events of the 2014/15 season. New Zealand's Sam Dickson (54) is second, while Argentina's Javier Rojas and Smith are next in line with 49 tackles each.Your top tacklers from the season so far @HSBC_Rugby @wernerkok1 leading the way for @Blitzboks @bokrugby pic.twitter.com/oThommH0FU— World Rugby Sevens (@WorldRugby7s) December 14, 2014World Rugby Sevens Dream Team for the Port Elizabeth tournament. Senatla and Cecil Afrika also made the team dominated by South Africans.The hosts trailed Fiji by two points coming into their home event, but now lead the standings with 59 points, with Fiji (51), New Zealand (47) and Australia (46) completing the top four places that would ensure automatic entry into the Olympic Games in Rio de Janeiro in 2016.The next tournament in the series is scheduled for Wellington, New Zealand on the weekend of February 6-7.