While refreshments are served, here's a reminder of the two Australia wickets to fall in the first hour.

Kagiso Rabada has 2-9 from his first six-over spell.

Vic Marks
Former England spinner on BBC Radio 5 Sports Extra

Marnus Labuschagne is here with his career struggling a little bit and Lord's could be another turning point for him.

Australia's selectors would be pretty chuffed with that outcome, @mardysim.

Steve Smith casually perches on his bat as Marnus Labuschagne plays out a maiden to Wiaan Mulder, who has replaced Kagiso Rabada.

Mulder beats the outside edge to finish the over. And that's drinks.

@mardysim on X: Couple of quick wickets for the Saffies. Excellent work.

326-2 at the close?

Image source, Rex Features

Jim Maxwell
BBC Test Match Special commentator at Lord's

It's quiet here at Lord's as Australia dig themselves in, but South Africa's bowling has been compelling as they make the batters play a shot with each ball.

How do you think Labuschagne's audition to be Australia's next opener is going, George?

Apart from that one edge which fell just short of Ryan Rickelton, he's been pretty solid I think. Strong leaves and running smartly.

He runs three to finish the 12th over.

A fourth maiden for Kagiso Rabada, with Steve Smith defending all the way. There's a couple of darts to suggest he's interested in the single but every time, he retreats.

Rabada has 2-9 from his six overs. Impressive.

Andy Zaltzman
Test Match Special statistician

There were 19 balls before Kagiso Rabada conceded a run and only once has he done better in his illustrious career.

He has a strike rate of a wicket every 39 balls in Test cricket. This is the best record from a bowler who has bowled 500+ in the history of Test cricket of which there are 292 bowlers.

Marnus Labuschagne tastes early success against Lungi Ngidi, easing a solid drive through the covers for four. So far, so good for the opener who moves onto 14.

A change in the bowling attack for South Africa, with Lungi Ngidi replacing Marco Jansen.

Image source, PA Media

Kagiso Rabada has quite the swagger as he walks back to the top of his run-up. He looks the least-hurried man in the world.

However, it's Steve Smith who gets the last laugh, punching the ball square to finish the over with a four. It just beats Tristan Stubbs to the rope.

Firdose Moonda
Cricinfo writer on BBC Radio 5 Sports Extra

That did fall short of Ryan Rickelton and South Africa didn't get too excited.

They've done really well this morning and this is what Temba Bavuma had in mind when he decided to bowl first.

How often have we seen Marnus Labuschagne and Steve Smith batting together for Australia? Smith is even more determined than his partner to have the sight screen shifted which causes a pause in proceedings.

Australia pick up two singles and South Africa finish the over with hands on heads as an edge from Labuschagne bounces just short of the fielder.

Andy Zaltzman
Test Match Special statistician

Usman Khawaja's duck is the third longest ever recorded in a Test in England.

Firdose Moonda
Cricinfo writer on BBC Radio 5 Sports Extra

This is exactly the start South Africa wanted. I was a little bit nervous when they decided to bowl first.

They've justified it so far. Some excellent overs from their bowlers.