Starc reached the milestone by beating Rassie van der Dussen for a duck with a trademark in-swinging yorker who sliced number three’s bat and pad and sent the Gabba crowd into a frenzy before lunch on the second day.
The 32-year-old pointed to the crowd as he ran onto the pitch only to be mobbed by his teammates.
Eleven years after his debut against New Zealand in Brisbane, Starc became the seventh Australian to claim 300 scalps in Tests, joining Shane Warne, Glenn McGrath, teammate Nathan Lyon, Dennis Lillee and Mitchell Johnson.
“He continues to impress,” said Cummins after Australia secured a six-wicket win over Proteas in two days.
“The longevity of taking 300 wickets in over 10 years – I think he’s still going to a different level. You’ve seen him (bowling) around the wicket, choking the ball. That’s a new skill for him. An absolute huge member of our team and he just keeps getting better.”
Starc finished with five wickets for the game, including the dismissal of Temba Bavuma for 38 in the first innings, which broke a 98-run partnership with Kyle Verreynne and triggered the Proteas’ collapse for 152.
Starc could have had his 300th wicket on day one when he had Kagiso Rabada hit straight over Travis Head, but the Australian number five juggled and then reversed the hold, prompting a groan from the crowd.
Starc said Head was the first to congratulate him on Sunday after beating Van der Dussen.
“Very cool, very privileged. I’ll think about it later, but it’s good to have a test wicket,” added the bowler. “Obviously the last 18 months to two years has probably been some of the best test cricket I played. So hopefully that can continue.”