It was Gregor Townsend’s side’s third victory in a row over the Wallabies, the first time they have achieved that feat since 1982, and also brought to an end the visitors’ own winning run which had stretched to five games and included back to back triumphs over South Africa, next weekend’s visitors to Edinburgh.
Scotland needed to show plenty of resolve and concentration, twice coming back as Australia edged ahead in the second half.
They had taken the lead through a first-half try from Hamish Watson but Rob Leota countered in the second period with a fine score. James O’Connor’s boot kept the scoreboard ticking over for the visitors but Finn Russell landed the decisive penalty in the 68th minute to restore Scotland’s lead, one which they were to retain until the end.
It was a joyous occasion for the majority of the 67,000-plus fans packed into the old stadium as Murrayfield hosted a capacity crowd for the first time in almost 20 months.
And they found a new hero to cheer in Ashman. The hooker was introduced in the 11th minute when George Turner was invalided out and the Sale Sharks seized his opportunity with gusto, plunging over for a wonderful try.
There were no points scored in the opening quarter but it was not for the want of trying. It was fast and loose with both teams keen to make the most of the perfect autumn conditions in the capital.
There was an early scare for Scotland when Russell had a kick charged down but Len Ikitau’s pass round the back went astray.
Australia had an opportunity to edge ahead after three minutes when Sam Skinner was adjudged to have come in from the side but O’Connor’s penalty attempt was well off target.
The early loss of Turner was a blow for Scotland but it meant an early introduction for Ashman, who stepped off the bench to win his first cap.
The Canada-born 21-year-old had been on England’s radar but opted for the country of his father and it didn’t take him long to make an impression.
Scotland were beginning to exert pressure and the Aussies were starting to creak, conceding a handful of penalties, each of which Scotland kicked to the corner.
They were getting little joy initially from the lineout option but that all changed in the 20th minute with a well worked try. Ashman’s throw was taken by Jamie Ritchie who quickly fed Grant Gilchrist. Watson then came piling in, plucking the ball from the lock’s grasp before crashing over for the try, his sixth for Scotland.
There was an anxious wait while referee Romain Poite checked for any potential blocking by the Scottish forwards but the Frenchman was happy to stick with his original decision after consulting the TMO. Russell knocked over the conversion to put the Scots 7-0 ahead.
The score had a galvanising effect on the Wallabies and they thought they had a try of their own as captain Michael Hooper stretched over beneath the posts after a period of sustained pressure.
However, it was ruled out when replays showed that prop Allan Alaalatoa had caught Matt Fagerson on the head with his swinging arm as he tried to clear out the Scotland No 8.
It was a big call by Poite and a disastrous double whammy for Australia as Alaalatoa was also yellow-carded.
Scotland were off the hook but the visitors were able to reduce the lead with an O’Connor penalty just before half-time.
And they moved ahead four minutes into the second period even though they had only 14 players on the pitch. It began with a scrum on the Scotland 22 and a smart break by sub Izaia Perese. The ball was recycled and Nic White picked out Rob Leota who ran the perfect line, evading the clutches of Pierre Schoeman and Duhan van der Merwe to score the try. O’Connor converted.
White then showed his value at the other end of the pitch, felling a galloping Van der Merwe with a superb tackle as the winger tore through. But Scotland had their tails up, moving the ball across the park at speed as they probed for an opening.
When it came it was via the big men in the front row rather than the backs and it was a special moment for Ashman. As Scotland recycled the ball, Schoeman passed to the hooker who launched himself towards the corner, touching the ball down while airborne to ensure he remained in play. It was a splendid bit of finishing from the debutant, worthy of a world-class winger. Russell’s conversion attempt drifted wide but Scotland had edged ahead 12-10 as the game entered its final quarter.
Injuries were causing all sorts of disruptions to the Australian pack but they were hanging in there and retook the lead when O’Connor slotted over a 40-metre penalty following an infringement by Jamie Ritchie.
Murrayfield was growing tense but there was an almighty roar when Russell landed a penalty with 12 minutes remaining to give the home side a 15-13 lead.
Still Australia came, but the Scots produced a tremendous turnover in the 76th minute to turn defence into attack, with Hogg bursting away before feeding George Horne.
It was to be the last time the Wallabies threatened and Scotland saw out the last few minutes in disciplined fashion before Horne, with the clock showing 80 minutes, booted the ball into touch to wild applause.