Pat Cummins and Nathan Lyon put Australia in the driving seat of the second Test at the Melbourne Cricket Ground on Wednesday to leave Pakistan tottering at 194-6, still 124 runs behind on day two.

At stumps, Mohammad Rizwan was on 29 and Aamer Jamal not out two after Cummins took the crucial wickets of Abdullah Shafique (62) and Babar Azam (one), then Agha Salman (five).

Lyon chipped in by removing Imam-ul-Haq (10) and Shan Masood (54), while Josh Hazlewood bowled Saud Shakeel for nine as Pakistan's dream of a first Test win in Australia since 1995 faded.

"I thought we bowled decently before tea without too much reward. They obviously batted quite well," said skipper Cummins. "But it was good at the end there to get a few big wickets and it feels like we're well into their order now.

"I was actually really happy," he added of Australia's batting performance. "I thought our batters did a great job to get us to 300, it was hard work."

The visitors claimed seven wickets in the morning session on a pitch offering seam and swing, restricting the hosts to 318.

Aamer Jamal spearheaded Pakistan's charge with 3-64 after Australia resumed on 187-3 after being sent into bat, with Marnus Labuschagne top-scoring on 63.

Openers Haq and Shafique made a positive start, surviving a series of loud appeals. 

But veteran spinner Lyon, fresh from taking his 500th wicket during the first Test in Perth, finally earned a reward when Haq edged to Labuschagne at slip.

Undeterred, Pakistan upped the run rate after tea with Shafique reaching his first Test 50 in Australia, and fifth overall, with a four off Mitchell Starc.

But his 90-run partnership with Masood was broken by Cummins, who showed sharp reflexes to stick out his left hand for a catch off his own bowling to end Shafique's stay.  

Fired up, he then clean bowled danger man Azam before Lyon returned to claim his second wicket when Masood miscued and Mitchell Marsh did well to hold a catch with the sun in his eyes.

Hazlewood took care of Shakeel before Cummins brought himself back and accounted for Salman, caught by wicketkeeper Alex Carey to leave Pakistan in trouble.

"As a batting unit, it hurts," said Shafique. "But I hope we will recover from this partnership that is going on now."

- Jamal strikes -

Labuschagne had been a rock on day one, digging in for an overnight 44 off 120 balls.

He padded up again alongside Travis Head on nine with the sun shining, smacking a boundary off Shaheen Shah Afridi in the opening over to signal Australia's intent.

The explosive Head drove Hasan Ali to the ropes off his first ball and followed it up with another in the same over to quickly get in the groove.

But his flair cost him on 17, lashing at a wide Afridi delivery that took a thick edge and was well collected by Salman in the slips. 

At the other end, Labuschagne kept plugging away to bring up his 17th Test half-century.

Marsh was given out twice in successive balls during a fiery Ali over while on seven by West Indian umpire Joel Wilson. He reviewed both decisions -- for lbw and caught behind -- and survived.

But just as the match appeared to be slipping away from Pakistan, Jamal bagged the wicket of Labuschagne, who edged to Shafique at slip.

Carey and Starc quickly followed as Pakistan cashed in with a new ball, before Marsh holed out to Jamal off Mir Hamza on 41 and the tail folded. 

Australia won the first Test of the three-match series in Perth by 360 runs.