Tea Pakistan 271 and 53 for 4 need 397 more runs to beat Australia 487 and 233 for 5 dec (Khawaja 90, Marsh 63*, Shahzad 3-26)
PERTH – Pakistan's top-order crashed on a tough Optus Stadium surface in a disastrous start to a record run chase as Australia eyed a first Test victory within four days.
Set 450, after Australia declared 30 minutes into the second session, Pakistan succumbed to brilliant bowling from quicks Mitchell Starc, Josh Hazlewood and Pat Cummins.
With the surface deteriorating, proving particularly difficult for batters combating deliveries rearing but also creeping low, Pakistan faced a daunting task to avoid a 15th straight Test defeat in Australia.
It went almost as expected with Pakistan blown away in the opening seven overs to slump to 17 for 3. Opener Abdullah Shafique was caught behind in the first over when he poked at a menacing Starc delivery outside off stump. It was Starc's 200th Test wicket at home as he bowled with far more consistency than in Pakistan's first innings.
Captain Shan Masood was dismissed for just 2 when he was caught behind off Hazlewood after driving loosely. It's been a tough captaincy debut for Masood, who made a breezy 30 in Pakistan's first innings but his team have been unable to play a proactive brand of cricket he promised ahead of the series.
Australia's full-strength attack has proven too tough to crack with attention turning to returning off-spinner Nathan Lyon, who is just one away from his 500th Test wicket. He took three wickets in the first innings in a successful return after suffering a calf injury that cut short his Ashes series.
Lyon entered in the 11th over, but was made to wait until after the tea break to attempt to reach the milestone.
Pakistan's hopes rested on talisman Babar Azam, who defied Australia's attack for almost 10 overs before he was helpless against a cracking Cummins delivery that seamed away to be caught behind.
Australia declared when Usman Khawaja was dismissed for 90 about half an hour after lunch. He faced 190 balls in a brave innings having overcome a painful blow to his arm to anchor Australia with all-rounder Marsh unbeaten on 63 from 68 balls.
It was a dogged performance from Khawaja having come into the match under the spotlight after not being allowed to wear shoes which expressed humanitarian views.
After lunch, with Australia eyeing a declaration, Marsh put the foot down and smashed quick Shaheen Shah Afridi for a cover boundary to reach his second half-century in his first Test match on his home ground.
The runs flowed at a speed not seen previously in the innings but the batters were still troubled by the occasional hostile delivery. Marsh was hit in the helmet from a Khurram Shahzad delivery that spat off the surface.
While debutants Shahzad and Aamer Jamal impressed throughout, Afridi struggled to find his pace and bowled mostly at a sedate pace in the early 130kmhs.
It capped a disappointing performance for Afridi who had been elevated as vice-captain ahead of the Test with much burden on him to lead an inexperienced attack. He dismissed Khawaja but finished with match figures of 2 for 172 from 45.2 overs.
Much like late on day three, batting was difficult in the first session with Steven Smith falling lbw for 45. Smith immediately reviewed and gestured that he thought the ball was going down the leg side. The DRS upheld the decision by the slimmest of margins with tracking confirming the ball would have clipped the bails.
Khawaja survived a thorough examination and bravely kept batting after copping a short length delivery from Jamal on his arm. It was reminiscent of the blows taken by Smith and Marnus Labuschagne late on day three, but Khawaja flourished after lunch to stretch Australia's lead to 449 runs.
Pakistan appeared to be imploding much like when they crashed to 72 all out in 2004 in their last Test appearance in Perth as they stared down the barrel of another defeat in Australia. – Courtesy ESPNcricinfo