The growth in South Africa paceman Marco Jansen has been exponential on and off the field.
The 22-year-old has taken 40 wickets in eight Tests at an average of 18, but he also told AAP that he's now three centimetres taller than he is listed on most cricket sites after having another growth spurt.
The 209cm left-armer impressed in the first Test at the Gabba where he took 3-32 in the first innings and will be crucial to the Proteas' chances of hitting back at the MCG from Boxing Day.
It is not surprising that he was a skilful provincial rugby union player in South Africa when he was 16, but the position he played is a surprise.
"I played rugby as a fly-half. I stopped when I was 16 or 17 and that is when I started growing," Jansen grinned.
"I am 209 centimetres now. That was the last time I was officially measured.
"I was 206 (cm) when I was 19 or 20 and that's what I said in my interviews at that time."
To get some perspective, Jansen is now six centimetres taller than former West Indies paceman Joel Garner who terrorised so many batsmen around the world in the 70s and 80s.
When 16, Jansen received a bursary at North-West University where his cricket "started taking off".
The Proteas had earlier invited Jansen to be a net bowler to help them prepare for Tests. He recalled seeing greats Vernon Philander, Dale Steyn and Morne Morkel at those sessions and wanting to follow in their footsteps. Now he leans on current trio Kagiso Rabada, Anrich Nortje and Lungi Ngidi.
"Learning off them is special for me and they have helped me quite a lot, especially when I have a few head worms going on in my head," Jansen said.
"When I have a few questions they tell me to keep it simple. I ask as many as possible. It is one thing to ask a question and get an answer, but another to go out and see what works and what doesn't.
"The challenge of testing myself against the best players in the world is what I enjoy most."
Jansen said his height was obviously a key to his success so far, but he's also smart about using it.
"In Australia there is more pace and more bounce but you have to figure out the length to bowl. It is about adapting to conditions," he said.
Rabada said Jansen was living up to the challenge.
"He is an X-factor bowler and so natural. Watch him bowl and it is like he could wake up at 3am and do what he did in the first innings (at the Gabba)," Rabada said.
"He is extremely natural. He's gifted. He's got height. He's got pace. He's got bounce. He can swing the ball. He can nip the ball. What more do you want? And he's a leftie. That's pretty rare."
