Jonathan Trott has played two Twenty20 matches for England
England batsman Jonathan Trott is not good enough to get into South Africa's team, their coach Mickey Arthur said.
Trott, 28, was born in Cape Town and played under-19 cricket for South Africa, but qualifies for England through his parentage.
He will make his Test debut in the decisive final Ashes encounter at the Oval on Thursday.
"I don't think at this moment in time Jonathan would be playing for South Africa," Arthur told BBC Radio 5 live.
"Our top six is fairly strong and pretty settled at the moment but he would certainly have been there or thereabouts and adding a lot of depth to our system and to our structures."
Trott has been brought into the England side in place of the out-of-sorts Ravi Bopara, and is set to bat at number three against Australia.
The series is tied at 1-1 and England must win to regain the Ashes.
Trott was called up to the England team in 2007, scoring just 11 runs in two Twenty20 matches against the West Indies.
He has been recalled on the strength of a fine season in the county championship, in which he has scored 1,013 runs at an average of 92.09.
South Africa are ranked second in the ICC Test Championship, three places above England.
Two of their batsman - Graeme Smith and Jacques Kallis - are rated among the world's top 10. South Africa-born Kevin Pietersen is England's highest-ranked batsman at number 14.