Shaun Pollock has backed South Africa to displace England at the top of the world Test rankings over the next six weeks, because he feels their bowling attack is slightly superior. But the former Proteas captain and all-rounder concedes that their lack of preparation is a concern, contrary to the insistence of Gary Kirsten, his old international team-mate who is now the head coach.

Kirsten argued that a two-day game against Somerset followed by a three-day fixture against Kent, both of which were rain-affected and neither having been especially intense, had left his players primed for start of the first Test at The Oval on Thursday. But Pollock, who toured England three times and will be covering this series as part of the Sky commentary team, said: "It is a bit of a concern. The test for all the batsmen on a tour of England is the late swinging ball and the ball nipping around off the seam. I don't think it's much of a concern for the bowlers, I think they can prepare wherever. It's just the batsmen and the surface they're going to face."

However Pollock, while admitting bias, was happy to provide the England bowlers with a little extra motivation. "I think South Africa will have the slight edge," he said, backing Dale Steyn, Morne Morkel, Vernon Philander, Jacques Kallis and Imran Tahir to carry a greater threat than James Anderson, Stuart Broad, Graeme Swann and Tim Bresnan, assuming he wins the nod as England's third seamer.

"It's a little unfair to analyse it because our guys, I know what they're capable of. Philander's been remarkable – his introduction to Test cricket shows he has the serious skills to perform at the top level so that really does complement Steyn, who's been a real success for so many years.

"Morkel always takes a little bit longer to get into a series than some of the other bowlers but he brings a different dimension with his pace and bounce. Jacques – we all know what he can do – and it's great to have that depth in the bowling and we've got Tahir who is a wicket taking option and can add a bit of guile to wrap up the tail. So I think they've got all the bases covered and I feel they will have the upper hand. With 15 days of sunshine I would back South Africa to win the Test series 2-1."

• Shaun Pollock commentates for Sky Sports during a summer of live cricket available on TV and via Sky Go for online, mobile and tablet devices