Scorecard and ball-by-ball details
First, win a session. Then another. Then win the day. And maybe, just maybe you might have a chance of winning the match. England have enjoyed few such small victories during this series, but on a day when they claimed Australia's last seven wickets for 67 runs, and Alastair Cook scored a drought-breaking hundred, and England finished the day comfortably at 2 for 192, it was obvious which team had taken the honours. For once, it wasn't Australia.
Of course, much work remained ahead for England. Australia's strong performance on Boxing Day set the platform for a total of 327, and by stumps England were still 135 runs behind. But their position - albeit with the Ashes already in Australian hands - was much healthier than it had been 24 hours earlier. Cook brought up his hundred in the final over of the day by swivelling a pull for four off Steven Smith's legspin, and finished unbeaten on 104 alongside Joe Root on 49.
Cook's performance was significant, for he entered this match having failed to post a half-century in any of his past 10 Test innings - the longest such drought in a career spanning nearly 12 years. Dead rubber though it may be, his free-scoring innings was highly encouraging for England, as he struck 15 boundaries and punished Australia's bowlers through point, straight back down the ground, through leg, and even with the occasional cover-drive.
By the end of the day he had not only made his 32nd Test hundred, he had also moved past Mahela Jayawardene and into eighth position on the list of all-time Test run scorers. The Australians shook Cook's hand as he walked off at stumps but they must also have rued giving him a life on 66 when he edged Mitchell Marsh and Smith, standing very close at first slip, failed to cling on to a challenging catch.
On a very hot day when the fast bowlers baked and Pat Cummins struggled with an upset stomach, it took a brilliant catch for Australia to claim their first wicket of the innings. For the second time in the series Nathan Lyon plucked a return chance with one hand, this time off the leading edge of Mark Stoneman, who had made 15.
James Vince would not have wanted to see replays of his dismissal when he returned to the rooms after making 17. Adjudged lbw off the bowling of Josh Hazlewood, Vince decided against a review, but Hot Spot showed that the ball had brushed his inside edge on the way through to his pad. His departure left England at 2 for 80, but Root and Cook settled in for a partnership that had reached 112 runs at stumps and solidified England's position.
Root played an important accompanying role and was within touching distance of his third half-century of the series. However, his inability to turn those starts into hundreds in the manner of his Australian counterpart, Smith, has been one of the key factors in the series.
The importance of Smith for Australia was reinforced when his dismissal early in the day sparked the collapse that resulted in the last seven wickets falling for 67. A no-ball from debutant seamer Tom Curran on the opening day had denied him David Warner on 99 as his first Test wicket, but inducing a chop-on from Smith, trying to force a short and wide ball through off on 76, was a fine replacement for Curran.
It was the first time Smith had been out in a Melbourne Test since 2014; he had scored 445 runs between MCG dismissals. Mitchell Marsh also dragged a wide one onto his stumps for 9 off the bowling of Chris Woakes, and Tim Paine later did the same on 24 while trying to pull James Anderson.
In the meantime, Shaun Marsh had passed fifty for the third time in the series, raising his half-century from his 130th delivery, but fell lbw for 61 to Stuart Broad via a well-judged review from Root. Jackson Bird, curiously promoted to No. 9 ahead of Josh Hazlewood and Lyon, was lbw to Broad for 4, leaving Australia at risk of failing to bat out the opening session.
They went to lunch on 8 for 326 and added just a single run after the break for the loss of their final two wickets, as Cummins edged Broad to slip for 4 and Lyon was trapped by Anderson for a duck. Anderson finished with 3 for 61 and Broad collected 4 for 51, his best analysis in a Test innings since November 2016. Throw in a Cook century, and it was the day on which England's old heads finally stood up to be counted.