Career-best Starc on the brink of another legacy-defining moment

Mitchell Starc might be in the midst of yet another legacy-defining moment.

While the left-arm quick is the ripe old age of 36, there's no doubt that last summer's Player of the Ashes is in career-best form, and now he's on the verge of leading Australia to another huge Test result in South Africa.

With Australia on the brink of humiliation early on Day 1 in Cape Town, it was Starc who rallied with six wickets in the final session to bowl South Africa out for 329.

Now, after removing both openers in South Africa's second innings, helping reduce the home side to 4/140 and just 40 runs ahead of the Aussies, it's been Starc who has done the damage again.

If Starc can get two more wickets to claim his fifth 10-wicket haul in such a massive series-deciding Test, Whateley thinks this Cape Town effort could comfortably sit amongst his most distinguished performances.

"They're so finely tuned, these fast bowlers at the moment, and they have committed themselves to it absolutely," Whateley said on SEN Captain's Run.

"Starc's the veteran, but he's in absolutely career-best condition, and he's having legacy moments.

"His Ashes series is obviously going to be lionised when the final story is written, but this Test match as well, if Australia go on to win it (will be up there).

"What he did in the final session when Australia had been taken to the brink on Day 1... he took six wickets in a session and four in the last six balls.

"Then he starts off on Day 3 and has two of the four wickets.

"I sincerely hope he gets two more and gets 10 for the match so it is always documented in his statistics."

While this match could go down in the record books for Starc, Whateley thinks numbers only tell part of the story of his late-career brilliance.

"But it'll be more than that, when you dig into what he's been able to do towards the end (of his career), the Ashes, now South Africa and the promise of what it might be in England and India as well," Whateley said.

"They're to be admired. The whole program has to be admired for the condition that they're in.

"I do feel like they deserve a result here, but sport doesn't always necessarily give you what you deserve.

"But they've given themselves every chance to really get it done on Day 4, I think."

Day 4 begins at 7:30 pm (AEDT) on Friday when Matthew Breetzke (19 not out) and Ryan Rickelton (8 not out) return to the crease.

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