Seller, winner of both races in the opening round at Phakisa Freeway in the Free State in March, looked set to repeat the performance after qualifying first and also winning the Top 15 Superpole on Saturday.
He followed this up with a close 0.09sec win over Haran in race one despite riding with a painful shoulder injury picked up in a motocross accident.
Third in race one was Lance Isaacs (Black Swan Energy BMW).
Seller led race two into the first corner, followed closely by Haran and Isaacs. He ran wide on to the grass at the top end of the circuit, caught out by tyres that hadn’t warmed up sufficiently, and dropped the Kawasaki.
He was not able to pick it up with his damaged shoulder and was forced to retire.
Haran went on to take the victory – his first in the SuperGP category after just four races – by 2.87sec from Isaacs.
Ronald Slamet (Mike Hopkins/Novel Ford Kawasaki ZX10) recorded his best result of the year with third place, a further 23sec back and just three tenths of a second ahead of Ivan van Niekerk (Recon Racing Kawasaki ZX10).
After the first two rounds, Seller, the reigning SA Supersport champion, leads the new SuperGP title chase with 75 points from Harran (71) and Isaacs (60).
There were also two different winners in the Super600 category with Cameron Petersen (EmTek/Brother Yamaha R6) winning race one after dominating qualifying and Anthony Shelly (Fercor Projects Kawasaki ZX6) taking the honours in the second of the two 12-lap races.
Petersen, the reigning SA Supersport champion, looked set to make it a clean sweep for the day only to be knocked out of contention in race two when he was caught off balance by a strong gust of wind on lap five while enjoying a comfortable four-second lead.
Shelly inherited a lead he was not to lose and crossed the finish line less than two-tenths of a second ahead of Dean Vos (EmTek/BrotherYamaha R6) and 3.67 sec in front of Stehen Odendaal (Portable Shade Kawasaki ZX6).
Odendaal leads the championship after two rounds with 79 points and is followed by Scholtz (60) and Vos (57).
The next round of the championship is at Cape Town’s Killarney circuit in the Western Cape on May 18.
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