Matt Prior insists England have not given up hope of winning the second Investec Test after rain and South Africa's openers repelled their push for victory on the penultimate day.

Kevin Pietersen failed to add to his overnight 149, an innings that single-handedly turned this match on its head, but Matt Prior's counter-attacking 68 helped the hosts to 425 all out, a lead of just six.

Hopes were high that England could force the initiative as Alviro Petersen, who struck 182 for the Proteas, would only bat if needed due to a hamstring strain, while fellow opener Graeme Smith and Jacques Kallis were carrying knee and back injuries respectively.

However, Smith, with strapping on his left knee, and makeshift opener Jacques Rudolph carried South Africa to 39 without loss from 17 overs before rain brought about an early finish.

"We know that if we come in hard tomorrow and put them under pressure, you never know what can happen," said Prior. "If we get a few early wickets, we've got an oppor-tunity to push hard and win.

"It's a bit disappointing to not get a bit more of a lead but, having said that, to get just ahead was good."

Prior hailed Pietersen's impressive knock, claiming the pressure is now on South Africa. Although England's seamers failed to take a wicket, their wicketkeeper-batsman felt they bowled well and that opening pair James Anderson and Stuart Broad were unlucky.

"Hats off to South Africa, they're a very good team and they've played very good cricket so far," Prior said. "But I think the way we bounced back yesterday, KP's innings was superb and we went ahead of them today.

"The way we went out and bowled was absolutely fantastic – Jimmy [James Anderson] and Broady [Stuart Broad] set it up perfectly. We were unlucky not to get a few nicks or a few wickets early on, but the pressure's now on them.

"It's probably the first time in this series they've had to soak up a bit of pressure, so if we can get a few early wickets then you never know what can happen."

Prior addressed his role in the team, insisting he is content to bat at No.7 with the lower order.

"As long as I'm scoring runs and contributing to the team then I'm happy," he added. "The balance of the side is far more important than any individual's preferences.

"There are times where you think 'I'd love to be out here a bit longer', but there you go. If I can contribute and play the role that's needed then that's where I'll play.

"It's a role I've had for a few years now, so I am comfortable and quite enjoy batting with the tail."