Cape Town - Proteas captain Hashim Amla hinted that spinner Imran Tahir might not be picked for the first ODI against Australia at SuperSport Park in Centurion on Wednesday.Tahir was a revelation for South Africa at the World Cup in India earlier this year. The leg-spinner claimed 14 wickets in five matches during the tournament and was lauded afterwards for his performances.But Amla told the Beeld newspaper that Tahir is not assured of his place in the starting XI."We haven't decided on the team yet. But if Imran gets the nod, it will be interesting to see whether he could achieve the same success in South African conditions."It's considerably different here (than on the subcontinent) and if it's cloudy tomorrow (Wednesday), it might be wise to pick an extra swing bowler," said Amla.Former Protea batsman, Boeta Dippenaar also expressed his concerns earlier in the week over Tahir's effectiveness in South African conditions. Dippenaar, who plays for the Knights, faced Tahir over the weekend in a SuperSport series match against the Dolphins at Kingsmead in Durban."After I faced him this week, I'm not so sure anymore that he's our best choice in South African conditions," Dippenaar wrote on his blog.