Mitchell Starc's triple-wicket maiden ripped apart South Africa's lower-order, put Australia on the brink of victory and has him just one wicket away from a maiden Test hat-trick.
With light fading fast in the final session on day four in Durban, Starc proved why he's one of the most destructive bowlers in the world when he removed Vernon Philander caught behind before he splattered the stumps of Keshav Maharaj and Kagiso Rabada with consecutive deliveries.
That was after the 28-year-old engaged in heated conversation and got in the face of Proteas No.6 Theunis de Bruyn for two overs, a sight Starc's teammates like to see.
"We enjoy it when Starcy is up and about like that and at the batters, because he bowls at high pace and can create chances all the time," Australia wicketkeeper Tim Paine said after play.
"It wasn't his session during the middle but he showed what he can do when the ball starts to reverse swing, or hopefully tomorrow when he gets the new ball in his hand.
"He's such a dangerous, fast, left-arm bowler that it's a delight to have him in your team."
Should Starc be called on to bowl in the morning by captain Steve Smith, he will have a new ball at his disposal with a Test hat-trick in his sights.
Starc is no stranger to taking three wickets in a row having captured two hat-tricks in the same game to bowl NSW to a remarkable Sheffield Shield at Hurstville Oval at the start of the summer.
A feature of the left-armer's performance at Kingsmead has been his ability to effectively generate and harness reverse swing with the old ball.
His five wickets in the first innings were captured with the old ball that was swinging unconventionally, while on Sunday his three wickets in the 80th over moved late in the air and off the seam.
Starc says it takes a group effort to get the ball in the right condition for reverse swing.
"It's a very abrasive surface, so it's trying to keep that shiny side nice and smooth and dry," Starc told cricket.com.au before play on day four.
"That's about it. We've got a couple of guys who look after the shining of the ball so as to not keep too many hands on the ball, especially when there's some sweaty hands out there.
"It's an important role that they play and especially us as bowlers to get stuck into the guys who aren't keeping the throws up as well."
Qantas tour of South Africa
South Africa squad: Faf du Plessis (c), Hashim Amla, Temba Bavuma, Quinton de Kock, Theunis de Bruyn, AB de Villiers, Dean Elgar, Heinrich Klaasen, Keshav Maharaj, Aiden Markram, Morne Morkel, Wiaan Mulder, Lungi Ngidi, Vernon Philander, Kagiso Rabada.
Australia squad: Steve Smith (c), David Warner (vc), Cameron Bancroft, Pat Cummins, Peter Handscomb, Josh Hazlewood, Jon Holland, Usman Khawaja, Nathan Lyon, Mitchell Marsh, Shaun Marsh, Tim Paine, Jhye Richardson, Chadd Sayers, Mitchell Starc.
Warm-up match: Australia beat South Africa A by five wickets. Report, highlights
First Test Kingsmead, Durban, March 1-5. Live coverage
Second Test St George's Park, Port Elizabeth, March 9-13. Live coverage
Third Test Newlands, Cape Town, March 22-26. Live coverage
Fourth Test Wanderers, Johannesburg, March 30-April 3. Live coverage