"They (the other props) give us a little bit of a headache because in terms of looking at what is our best option on the bench. But that's what you want from players, you want them to give you headaches so that's quite positive."
Smal readily accepts that Ireland will need to at least match the performance level of last March's memorable Six Nations win over England if they are to get the better of Australia in Auckland.
"It's the type of game that we want to put together and that we work towards all the time. We're not satisfied with less than that. That's the kind of standard that we want to maintain continually.
"(As coaches) you have to get the balance right, putting enough pressure on but also just keeping the players' confidence high all the time and letting them realise what they have, because they have something special in the team and you just need to bring it out.
"I think if you can cut down a little bit on the mistakes you can build a little bit more momentum and it's a different ball game then."
The big South African is unconcerned about Ireland's recent run of inconsistent displays. Early tournament nerves have been a factor, he says, for a number of teams.
"(Form) can turn very quickly. Obviously, the first World Cup game is always a nervous start, it's not just us, all the other teams," he explained.
"It is easy to say in hindsight but maybe if we could have finished a few more opportunities we got, and kicked a couple of penalties we got, that would have extinguished the Americans' fire a little bit."
Smal was satisfied with Ireland's set piece game in their Pool C opener, but wanted a better variation between mauling and using quick lineout ball off the top.
The breakdown is an area that will command much of the pre-match focus this week, especially with Wallaby openside David Pocock regarded as one of the best ruck operators in the world.
Smal wants Ireland to be quick and effective at the breakdown against Australia, something which they struggled to do at times during the win over the USA.
"I think there were some good things but the latter part of the game they maybe weren't as accurate and that's the one thing we have to get right for next weekend, to get the breakdown sorted out.
"Especially with Pocock, because he is one of their key guys and what he does quite well is slow your ball down, even if he doesn't get the ball.
"What he does is he takes the tackle and stands up in that space. So we have to get rid of him as quickly as we can and see that we get enough numbers to the breakdown.
"You want to have the ball carrier plus three, so at least four to the ball all the time, with your scrum half. So that's one area we want to get right and it's probably an area Australia will target, I think.
"They will target our pack and they'll target our back-line. Those are the challenges for us," he added.
New Zealand referee Bryce Lawrence was in charge of England's pool win over Argentina last weekend, and will be the man in the middle for Ireland's clash with the Wallabies.
Full-back Geordan Murphy noted Lawrence's tighter interpretation of the breakdown in that game, admitting: "I liked the way he refereed it, to be honest. He wanted a quick game.
"If you cleaned someone out and stayed on your feet that was fair. If you went off your feet, you were penalised. We watched it in the team room.
"The way England have been playing in the last few weeks is they've been playing right on the edge. They've been flying into rucks very hard and fast but probably not noses up.
"They've been noses down, they've been making some big hits. I think they've probably got away with a little bit in the last few weeks and Bryce Lawrence said no.
"Ireland don't ruck like that. We don't fire in head down. We're more technically correct, so we'll see how he referees it this weekend."
Follow the Ireland team in New Zealand on www.twitter.com/irfurugby.