"There were decisions that were got wrong using referrals."

It was the first time both teams had played using the experimental system which allows both teams a maximum of two unsuccessful referrals an innings.

"You've got to have all the technology available to make it work," said Smith. "It needs to be a lot more conclusive than it is at the moment. If you're only using technology in a half-hearted way you're just going to increase the frustration."

The South Africans made three unsuccessful referrals in the first innings, then failed to ask for a review when Australian batsman Phil Hughes twice gloved catches to wicketkeeper Mark Boucher and was given not out.

Australian captain Ricky Ponting said he was happy with his first experience of the system. "I said going into the game that we shouldn't expect every decision to be perfect. What we're after is to eradicate the really bad decisions."

Ponting said the system put pressure on captains. "It's a challenging thing for a captain because you've got to react so quickly. You've got to talk to the wicketkeeper, talk to the bowler. There's probably a bit of an art in the way you use the referrals. I think it's going to be a bit of a trial and error thing."