The first day of Australia’s Test summer began with Mitchell Starc striking in the opening over. It ended with David Warner racing to a brisk half-century.In between, South Africa faltered and fought back, but not enough to be comfortable with their position at stumps. Four years ago they won at the WACA having been bowled out for 225 in the first innings.This time they reached 242, but Warner’s late-afternoon efforts ensured Australia were firmly on top.It was not what Faf du Plessis would have envisaged from the day, after he won the toss on a good pitch for batting. Still, South Africa’s recovery from 4 for 32 meant they were still in with a chance in the match.And they had two of their most inexperienced Test batsmen - Quinton de Kock and Temba Bavuma, in their 11th and 12th Tests respectively - to thank. Had Vernon Philander not overstepped early in Australia’s innings, things could have been very different.On 17, Warner survived an lbw shout from Philander, who convinced du Plessis to ask for a review. Indeed, the ball was pitching in line, hitting in line, and the decision would have been overturned - except it was a no-ball.Eventually, Warner went to stumps unbeaten on 73 with his new opening partner, Shaun Marsh, on 29 and Australia’s total had moved on to 0 for 105. It meant their deficit was already eroded to 137.Warner has always been a massive threat at the WACA. His first Test innings at the ground - a blisteringly fast 180 against India in 2011-12 - was a sign of things to come.By stumps, he was only six runs away from overtaking Matthew Hayden as the all-time most prolific Test opener at the venue, no mean feat considering he has played barely half as many WACA innings as Hayden, who broke the Test record score there with 380 against Zimbabwe.He drove hard when South Africa’s bowlers overpitched, and cut when they fell a fraction short. Remarkably, 62 of his 73 runs came through the off side. At the other end, Marsh needed to do little but rotate the strike.Dale Steyn bowled quick, reaching 150kph, but was not consistent enough, and Kagiso Rabada took a little while to find his best. Philander was perhaps the best of the bowlers, but wasted his best chance with a no-ball.By stumps, Australia’s openers had a century partnership, something that no pair achieved during the South Africa innings.There was, in fact, only one half-century stand, the 71-run combination from Bavuma and de Kock, which came after some serious top-order wobbles.For the 19th time since the start of last year, Starc struck in the first over of an international innings. This time his victim was Stephen Cook, who had been in shaky form during South Africa’s warm-up matches against second-string opposition.It was no preparation for facing Starc with the new ball. The fourth delivery moved away just enough and Cook’s edge was taken by a diving Mitchell Marsh at gully.A bigger blow was to come for South Africa in the fourth over, when Hashim Amla was done by the subtle variations in Josh Hazlewood’s swing.Amla’s edge was comfortably taken at second slip by Steven Smith. It was the second duck of the innings, and South Africa were 2 for 5. Hazlewood also muddled Dean Elgar, who couldn’t decide whether to play or leave, and did neither, feathering behind to Peter Nevill.A fourth wicket was to come inside the first hour, when Peter Siddle moved one back in to kiss the inside edge of JP Duminy’s bat on the way through to Nevill.Du Plessis and Bavuma saw South Africa through to lunch without further loss, but du Plessis did not last long after the resumption. On 37, he edged Starc to Adam Voges at slip, and at 5 for 81, South Africa still looked in danger of a seriously sub-standard total.De Kock and Bavuma worked solidly at building the score up past 150, and Bavuma reached his half-century from his 84th delivery.It took an outstanding catch to end Bavuma’s innings, his inside edge off Nathan Lyon brilliantly snapped up by Shaun Marsh, lunging to his right at short leg.It was a key moment for Australia, as South Africa were threatening to undo all of Australia`s good work from the morning session.De Kock played his shots when the opportunity arose and found some support from the lower order, but wickets still fell regularly.Philander played on for 10 trying to pull Starc in the final over before tea, debutant Keshav Maharaj holed out to long-on off Lyon for 16, and de Kock missed the chance for a century when he pulled Hazlewood to Shaun Marsh at midwicket on 84 from 101 deliveries.It was a fine innings, but one that might not even cancel out Warner’s runs.The innings ended with Steyn bowled by Starc for 4. Starc finished with 4 for 71 and bowled with impressive pace throughout the day, given his very limited match practice after recovering from a nasty leg injury suffered at training in September.Hazlewood and Siddle were both accurate and found enough movement to trouble the batsmen, and Australia’s fielding was generally outstanding.Australia’s home summer usually begins at the Gabba - or the Gabbatoir - where they have not lost a Test since 1988.Their record at the WACA is much more mixed, but after one day of the Test season, they have made a fine start regardless of the venue.Source: ESPNcricinfo