Michael Clarke, Australia’s Test vice-captain, says Kevin Pietersen remains a huge threat for Australia during the Ashes despite his poor recent form. Pietersen, who is playing in South Africa to fine-tune for the series, was dropped for the one-day internationals at the end of the English summer.Clarke refuses to believe Pietersen’s powers have waned. “He’s a big player, he’s a match-winner and I think he’s one of those guys where if you’re England you’ve got to have him in your team,” Clarke told AAP. “He’s had a lot of success in all three forms of the game and I think he’s one of those guys in big series who you want in your team.”Clarke said Pietersen would be frustrated by his form – he faced two balls in his opening game in South Africa – but is too good to be in the slump for a long period. “In any team if you can keep one of their main players not scoring as many runs as they would like, I think you’re doing a really good job as the opposition,” Clarke said.”I guess like Punter [Ricky Ponting] for us, England will be very focused on trying to minimise his impact in the games and we’ll be doing the same for a few of their guys, but Kevin Pietersen will be one of them.” Unlike the previous tour, Andrew Strauss’s squad has a full list of tour games to give their players the chance to be in peak form before the opening Test at the Gabba from November 25.