Steve Smith passes Joe Root's catching record as Australia take a 139-run lead in Durban

Steve Smith became the most prolific catcher in Test history outside the wicketkeepers as Australia closed the third day at Kingsmead 139 runs in front

Smith held four catches as South Africa were bowled out for 284 in reply to Australia's 390, and the second of them was his 221st in Test cricket, one more than the 220 Joe Root had taken to hold the record for a non-wicketkeeper.

Australia, who chose to bat on the opening morning, led by 106 on first innings and were 33 for 0 from 5.4 overs when bad light ended play for the third day running, Nic Maddinson unbeaten on 17 and Travis Head on 10.

With two days left in the first of three Tests, and the ball yet to behave unpredictably at Kingsmead, Australia are the side with a result to chase.

The catch that broke the record

Smith reached 220 when Temba Bavuma went back to a reverse sweep off Nathan Lyon and picked him out for 3, a dismissal that drew him level with Root.

The record came two wickets later. David Bedingham, South Africa's top scorer with 49, pushed at Pat Cummins and Smith dived full length to his left to take it, his 221st catch in the field.

He got there in his 126th Test and his 240th innings in the field. Root needed 169 Tests and 323 innings to reach 220, so Smith has gone past him 43 Tests and 83 innings sooner.

"He's an absolute freak," Lyon said of a team-mate who now sits clear of Root, Rahul Dravid on 210, Mahela Jayawardene on 205 and Jacques Kallis on 200.

Three wickets for 15 runs undo South Africa

South Africa had begun the morning in reasonable order, Aiden Markram and Bedingham scoring at better than four an over and Bedingham taking three boundaries in a row off Mitchell Starc.

Markram's dismissal started a slide of three wickets for 15 runs that left the home side 99 for 4, and they went to lunch on 115 for 4 with Tristan Stubbs on 14 and Wiaan Mulder on 7.

Cummins then removed Stubbs for 32 and Mulder for 30 within two overs, both hooking or pulling at the short ball, and Josh Hazlewood had Marco Jansen caught at mid-off attempting the same stroke.

A tail that would not go away

South Africa were 238 for 8 at tea, still 152 behind, and it was the lower order that kept the deficit within range.

Simon Harmer finished 35 not out, Keshav Maharaj made 34 and Anrich Nortje 16 before Beau Webster dismissed him to end the innings at 284 in 78 overs.

"Every time we looked like getting something going, we lost a wicket," South Africa's batting coach Ashwell Prince told reporters.

Maddinson and Head waste no time

Australia sent in Maddinson and Head rather than protect a nightwatchman, and Maddinson hit the first ball he faced, from Jansen, for four before lifting Mulder over the leg side for six.

The pair scored at just under a run a ball for the 5.4 overs available to them, a tempo South Africa expect to see repeated.

"We might see a lot more of what we saw this evening from their approach," Prince said, adding that his bowlers would have to control the run rate and grind Australia down rather than wait for errors.

The light is the obstacle

Play has been cut short by gloom on each of the first three days, and Durban's early sunsets and afternoon cloud are a larger threat to Australia than the pitch.

South Africa's plan for the fourth day is containment, in the hope that the overs Australia need to bat and then bowl them out are simply not there.

Australia, 139 ahead with ten wickets standing, will want to set up a fourth innings early enough to use whatever light the match has left.

Scorecard: Australia 390 (137.2 overs) and 33 for 0 (5.4 overs); South Africa 284 (78 overs). Australia lead by 139 runs at stumps on day three.

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