England’s No 5 finished unbeaten on 110 after sharing an unbroken partnership of 174 with Jonny Bairstow (75no).
It was a day England dominated, closing at 305-4, despite some fast and aggressive fast bowling from Australia’s trio of quicks.
Mark Stoneman (56) withstood some particularly hostile pace was hit on his helmet with a Josh Hazlewood bouncer, had his bat broken by Mitchell Starc and was dropped twice.
But it was the partnership between Malan and Bairstow which took England from 131-4 to over 300 at the close – England’s best stand of their tour – which rightfully will take the headlines.
Malan has shown glimpses of form in his seven Tests to date – hitting half centuries against West Indies last summer and again in Brisbane. He also reached three figures in the first class tour match in Townsville against a Cricket Australia XI.
But his innings yesterday was not only classy and courageous – using his feet to Nathan Lyon and driving and pulling the fast bowlers at will – but a resounding vindication of selector’s faith.
It was largely chanceless as well with a couple of swings and misses outside off stump to Starc and Cummins and a top edged six off the former, his only loose shots.
Bairstow deserves great credit for playing the role of understudy to perfection for all that he gave Australia more hope than Malan with some lapses in patience.
Yet the most significant fact in the day was the number of overs England managed to put into the Australian fast bowlers’ legs with Starc (19), Hazlewood (20) and Cummins (21).
Key to that was England’s treatment of Nathan Lyon who was never allowed to settle or dominate.
It helped England that this was a good pitch to bat and that Root called correctly at the toss winning his third in a row.
Had it not been for Malan and Bairstow England might have been pointing to two more failures for Alastair Cook (7) and Joe Root (20) as reasons for why the Ashes were slipping out of their fingers.
They would no doubt have pointed to a hugely controversial DRS over-rule from Aleem Dar which sent Mark Stoneman (56) on his way on the flimsiest of evidence as a turning point not only of the day but perhaps the series.
Stoneman had survived a brutal examination of his nerve and protective equipment, struck on the helmet, gloves and seeing Starc break his bat handle with only the second ball of the day.
He had also ridden his luck during a hostile period of pressure from the Aussie quicks, getting dropped twice – by Mitch Marsh at slip and Nathan Lyon diving forward at point/gully either side of a ball from Hazlewood pinged him with vicious bouncer on the side of his helmet.
Stoneman battled really hard for his second century of the series, rescuing a tricky situation after Cook fell early, pinned in his crease with a full ball from Starc, leaving England 28-1.
Stoneman put on 71 for the second wicket with James Vince (25) and then dug in through a really difficult period after his captain Root gloved a delivery down the leg side to leave England 115-3.
When he departed England will have been chewing their nails. Joe Root and Paul Collingwood looked seriously hacked off at the overrule. They were smiling by the close.