South African great Jacques Kallis believes the decision to appoint Steve Smith as Australia’s Test captain is a smart one, but warned the 25-year-old he faces a steep learning curve.

Kallis retired after a brilliant international career last December having made 166 Test appearances for the Proteas with more than 13,000 runs and 292 wickets to his name, cementing his status as one of the greatest all-rounders to play the game.

The 39-year-old is in Australia to play for the Sydney Thunder in the Big Bash League but has never faced Smith in the Test arena.

However, he was impressed with what he saw from him during this year’s series win in South Africa by Michael Clarke’s side, where Smith scored two centuries.

Smith was appointed stand-in skipper for the remainder of the summer on Monday after Clarke was forced out of the series with India due to a torn hamstring picked up in the opening Test in Adelaide.

“It’s sad that Michael is missing out through injury but it opens the door for a guy like Steve and I think he’ll do very well,” Kallis said.

“It is tough, and it can take strain and when you are going through a bad patch you always have media conferences and that kind of stuff.

“That’s where the tough part is. There will be some very new challenges, but he is the type of character that will be able to deal with it.”

Clarke, who is also battling a degenerative back problem, said after the thrilling 48-run win on Saturday that he may be forced into early retirement, which ultimately led to the decision to appoint Smith.

Vice-captain Brad Haddin was widely expected to be handed the reins, but Kallis said he wasn’t surprised to see the young Sydneysider given the job.

“Obviously it was a close-fought battle between the two of them and they took the decision to go longer-term with Smith,” he said.

“Either would have done a good job and Steve will benefit from the experienced players around him and will lean on them at the start..

“But he has more than enough cricket knowledge to do a successful job.”