Morkel, playing in his final series before retiring from global cricket, claimed the wicket of Australian left-hander Shaun Marsh for 26 in the third Test at Newlands to become the fifth South African to take 300 scalps in the five-day format.
Morkel, who is retiring from global cricket after the series, took three of the first four Australia wickets to fall and became the fifth South Africa player to join the 300 club.
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Warner and South Africa's Quinton de Kock nearly came to blows in a heated off-field confrontation near the dressing rooms in the first test. Rabada was banned, and then overturned his ban, for aggressive and over-the-top celebrations in the second game.
Morkel, 33, playing in his 85th Test, took a fourth wicket when Lyon's adventurous 38-ball innings was ended by a catch by Dean Elgar running back from point.
Former Australia batsman Lehmann said he has never experienced the sort of abuse about players' families or other halves that his side have faced in this series. "You can have banter, that's good fun, but it's gone too far here".
Warner fired back. The pugnacious opener whacked three-consecutive boundaries and a six off Rabada as he raced to 30 in 13 balls.
"I think it [the abuse of our players] has been disgraceful", Lehmann said.
"You are talking about abuse of players and their families, it's not on anywhere in the world". "You just can't afford to play loose cricket".
Vaughan, never one to miss out on an opportunity to troll the Aussies, joined the debate as well: "It's making me chuckle the Aussies are making an official complaint about the personal abuse they are receiving. It shouldn't happen. There's been various incidents throughout the test series but this one has taken the cake".
Opening batsman Elgar had scored 106 when De Villiers was dismissed and batted with more fluency than usual.
That left Elgar not out on 141, having carried his bat for the third time in his Test career.
He was out three minutes before the interval though when he chipped a Mitchell Starc (1-35) delivery to Pat Cummins at mid-on.
Four balls later, the spinner repeated the dismissal as Morkel (4) was also gobbled up by Smith, a fifth catch of the innings for the Australian to equal the most ever in test history, one of 11 outfield players to achieve the feat.
The tourists will resume at 9-245 on day three, trailing the hosts by 66 runs.