To see Pat Cummins up close, it's hard to believe he is only 18. Tall and broad-shouldered, he is physically imposing for such a young man. Like most bowlers with genuine speed, he talks of how he enjoys seeing the fear in batsmen's eyes, how he loves to see them jumping about at the crease.

It is only when he speaks of his cricket-watching memories that his age truly registers. His idols were not the bowlers of Craig McDermott's era, but men like Stuart Clark and Brett Lee, who still hold playing contracts. Cummins was 13 when Glenn McGrath last wore the baggy green.

This Thursday at the Wanderers, Cummins could become Australia's second-youngest Test debutant of all time. Choosing the starting line-up for this match will be the final act of Andrew Hilditch's selection panel. By picking Cummins they would go out with a bang.

Although Australia's batting was the key problem in their Cape Town disaster, the bowling in the second innings also disappointed the captain, Michael Clarke. Peter Siddle was the last of the fast men chosen for that Test and could be the first one out, although Mitchell Johnson was less threatening than Siddle at Newlands.

Cummins has shown in the nets that he can trouble even the best of Australia's batsmen. Before the ODI in Durban late last month, he struck Michael Hussey on the body and left a bruise so painful that Hussey was still talking about it a fortnight later.

Although Cummins has played only three first-class matches, the selectors are confident his body can handle five-day cricket. Late last summer, Cummins bowled 33 overs in the first innings of a Sheffield Shield match in which Western Australia's Marcus North scored a century. North described Cummins' work as the most sustained fast bowling he had experienced since his Test career.

A week later, Cummins bowled 48 overs in the first innings of the Sheffield Shield final, and 65 for the match. He is confident Test cricket will not be a stretch.

"Yeah I think so," Cummins said when asked if he was ready for Test cricket. "Just watching the last few games and training hard over the last few weeks I think I've started to become closer to being ready but I guess you never really know until you're out there and bowling. I'm sure if I do get the chance it will be a good support group around the side and making me feel comfortable."

Cummins is already used to big leaps. On this tour, he made his ODI debut having not yet taken a one-day wicket for his state. He has nine first-class victims to his name. McGrath was also rushed into Test cricket, relatively speaking, but he still had 32 first-class victims at the time.

Not that the metronomic McGrath is the template for Cummins. Fast outswingers are the key weapon in Cummins' artillery, along with his quick bouncers, and Dale Steyn is arguably the world's best at that combination.

"I hope I am a similar bowler; he's obviously unbelievable," Cummins said of Steyn. "He's just about the best bowler in the world at the moment. He's incredible. I've never really studied him but it's always the aim to bowl fast and fast outswingers and he obviously does it very successfully so I guess he's someone you look up to and really try and strive towards."

While swing is an important part of Cummins' style, his speed is what initially made the selectors take notice. He is already breaking the 150kph mark. His pace was honed in the backyard against his two older brothers, Matt and Tim, both of whom have played first-grade cricket for Penrith, the Sydney club where Cummins burst on to the scene. A wicketkeeper, Tim went from facing Pat in the backyard to feeling his fast deliveries thud into the gloves.

"Growing up I was always trying to be a fast bowler and always a bowler as a kid," Cummins said. "It's probably only in the last couple of years where I've grown a bit more and got a little bit stronger the speed started to pick up a bit. It's great seeing the fear in the batsman's eyes. As a kid there was nothing more exciting than seeing someone like Brett Lee charge in and really give it to the batsmen and you could see the batsmen jumping around and looking pretty uncomfortable."

There could be a few South Africa batsmen feeling that way if Cummins plays at the Wanderers. Hussey might not be the only man to end the tour bruised by Cummins.