Bedingham is beaten as he tries to cut the short ball from Starc angled across courtesy of some extra bounce.
The next ball is full and this time Bedingham gets it off the middle, driving it straight back past the non-striker for a four.
He pushes the fifth ball into the off-side for a quick single and Bavuma defends the last ball.
Australia make a change as Nathan Lyon comes into the attack, to bowl the 37th over.
Lyon from round the wicket with a slip and short leg in place. Bedingham keeps out the first three balls before he takes a single and Bavuma blocks the last two balls.
Cummins back from the other end. Bedingham has shown a lot of patience, he has a lot of experience in these conditions courtesy of playing county cricket for quite a few years.
He defends the first three balls before he is beaten as Cummins manages to get the ball to hold its line and he inside edges the last ball for one.
Lyon from over the wicket as Bedingham does well to play late nad with the spin, defending the off-spinner on the leg side.
The last ball turns sharply and also bounce as Bedingham fends it on the leg side.
Against the run of play, Cummins strikes with the key of Bavuma. The South Africa captain plays the uppish drive as Marnus Labuschange comes up with a stunning catch in the covers, diving full length to his right to pouch the ball.
Bavuma walks back after a good hand of 36 from 84 balls, having put on 64 for the fifth wicket to get South Africa back on track.
Kyle Verreynne walks in at No 7. South Africa will need another good partnership to get close to Australia's first innings total.