A superb day's cricket from Australia saw them pull off an unlikely victory over Pakistan in the Boxing Day Test at Melbourne.

After four days plagued by rain, Australia were still batting in their first innings when the day began, but aggressive knocks from captain Steven Smith and Mitchell Starc saw them build a lead of 181 before declaring on 624 for eight.

The bowlers then took over as Starc and Nathan Lyon took three wickets apiece to wrap up the victory by an innings and 18 runs.

Starc was in particularly assertive mood, and he clubbed seven sixes before being caught when going for another off Sohail Khan, departing for 84 which came off just 91 balls.

When Lyon was out for 12 from eight deliveries, Smith - not out on 165 - set off sprinting for the dressing room to get in four overs before lunch.

The decision paid off as quick wickets either side of lunch left Pakistan rocking. Josh Hazlewood removed Sami Aslam for two in his first over before Starc pinned Babar Azam lbw with the first ball after the break.

Mitchell Starc took four wickets for just 36 runs as Australia wrapped up an unlikely victory (Getty)

Azhar Ali and Younus Khan took the score to 63 before Younus became Lyon's first victim, with the ball just carrying to Peter Hanscomb at short leg to send him back for 24.

Moments later Misbah-ul-Haq was out for a duck as Lyon struck again, tempting the Pakistan skipper into a reverse sweep.

Asad Shafiq looked more comfortable at the crease but Australia got rid of him with a bit of luck as Handscomb bobbled at chance twice at short leg before holding on to give Lyon a third wicket.

Then the big wicket fell when Hazlewood got Azhar lbw for 43, leaving Pakistan on 101 for six.

Sarfraz Ahmed and Mohammad Amir provided the sort of resistance the tourists needed, building a partnership worth 42, but Jackson Bird finally cracked the code.

Australia dismissed Pakistan for just 163 in their second innings (Getty)

Having just survived a big shout when Australia felt he had edged behind, Amir played on two deliveries later to go for 11.

Starc then got rid of Sarfraz, getting one through the gate to find his off stump and send him back for 43, leaving Pakistan on 153 for eight.

Starc repeated the trick as Wahab Riaz was out for a duck, and the Australian then wrapped it up with the wicket of the scoreless Yasir Shah as the tourists were bowled out for 163.