Johannesburg - The South Australia Redbacks wrapped up their Airtel Champions League Twenty20 (CLT20) league matches with their fourth victory on the trot, beating bottom of the log Guyana by 15 runs at the Wanderers Stadium on Tuesday.They are now guaranteed top place in group B and a semi-final at Centurion.It could have been very different. Guyana, who won the toss and put South Australia in to bat, kept the South Australians in check for the first 10 overs, restricting them to 82 for three. At one stage, South Australia were reeling on 41 for three, with tournament top scorer Michael Klinger out for 16.But some strange bowling decisions and some poor bowling allowed the Redbacks to add another 109 runs and amass 191 runs – one of the highest scores in the tournament so far, with Callum Ferguson (55) and Cameron Borgas (48) contributing the lion’s share with a fourth wicket stand of 88 off 62 balls.Paul Wintz took two for 11 in three overs, claiming the wickets of Daniel Harris and Graham Manou, but he inexplicably did not complete his four overs. Instead, Steven Jacobs, who did not bowl well, was given three overs, and went for 50 runs.Until the last few overs, Guyana were always in contact with the required run rate, in fact needing fewer balls for the first 100 than South Australia had taken.But they lost wickets at regular intervals, with Daniel Harris taking three for 33, and Daniel Christian weighing in with two for 20. Ramnaresh Sarwan one again made a valiant effort to keep his team in with a chance, smashing 70 off 46 balls, but he was finally caught by Tom Cooper off Harris in the 19th over, and that was game, set and match. Guyana go home without a single victory, while the Redbacks have yet to lose a match.