PERTH, Australia, Dec 17, 2023 (BSS/AFP) - Usman Khawaja and Mitchell Marsh steered Australia to an ominous 402-run lead over Pakistan on Sunday, with the home side zeroing in on another commanding Test victory against the South Asian side.

They resumed at 84-2 on day four of the opening Test at Perth Stadium and by lunch had battled to 186-4 ahead of a likely declaration later in the day.

Khawaja was unbeaten on a fighting 68, with Marsh not out 42, in a partnership worth 79.

Opener Khawaja began on 34 and Steve Smith 43 after the hosts bowled out Pakistan for 271 on the cusp of tea Saturday, well short of Australia's first innings total of 487.

But on a deteriorating pitch with cracks appearing, it was hard going early on Sunday, with Pakistan's pace bowlers beating the bat and causing problems.

Impressive debutant Khurram Shahzad got a breakthrough in the fourth over of the day, trapping Smith lbw for 45 with a ball that nipped back.

Smith reviewed but replays showed it clipping the top of the bails with the Australian veteran shaking his head and muttering to himself as he trudged off.

Enter the aggressive Travis Head, who stroked a straight drive boundary off the second ball he faced to signal his intent.

But he lived dangerously and a misjudged drive off Aamer Jamal went straight to Imam-ul-Haq at cover, out for 14.

Both Marsh and Khawaja survived reviews in the same eventful Jamal over as Pakistan ratcheted up the pressure.

Marsh hit sixes off Jamal then spinner Agha Salman to keep the scoreboard moving, before a huge escape on 23 when skipper Shan Masood dropped a sitter at mid-off.

At the other end, Khawaja kept grinding away to make a 25th Test half-century off 151 balls before accelerating once he reached the mark.