Australia 505 for 8 (Khawaja 160, Carey 93, Smith 72, Faheem 2-55, Sajid 2-151) vs Pakistan

Captain Pat Cummins resisted declaring late on day two of the second Test with Australia preferring grinding a weary Pakistan into the ground, as they passed 500 in their first innings on a Karachi pitch showing signs of deterioration.

Australia reached the close in a commanding position at 505 for 8 with Mitchell Starc 28 not out and Cummins yet to score. Starc and Alex Carey batted almost through the entire final session in an attempt to break the back of Pakistan, who have spent two whole days in the field but in-form openers Abdullah Shafique and Imam-ul-Haq were surely relieved not to have faced a tricky period before stumps.

Cummins is set to face scrutiny for not sending Pakistan in late on the day although Australia gave a clear indication they want to bat just once in this pivotal match in a belief the pitch will deteriorate further. Australia batted their highest number of overs in an innings in Asia since 1956, but inconsistent bounce and sharp turn was evident later in the day.

Carey fell for 93 just before stumps and agonisingly short of his maiden century after batting fluently to energise an otherwise dull final session, where everyone was seemingly waiting for Australia's declaration but it never came.

Australia's indefatigable innings was dominated by Usman Khawaja's brilliant 160 off 369 balls as he fell just short of his highest Test score of 174 against New Zealand at the Gabba in 2015. His 11th Test century - and first in the country of his birth - was marked by unwavering concentration, but he could only score 33 runs off 103 balls on day two underlining the changing nature of the pitch.

Khawaja's innings ended midway through the second session when he was bowled by a cracker of a delivery from offspinner Sajid Khan, who produced drift and sharp turn to hit the top of off stump.

After a memorable first innings in the city his family hails from, the 35-year-old departed to a standing ovation from a boisterous crowd having become the first Australian Test centurion in Pakistan since Mark Waugh's 117 in Peshawar in 1998.

Eyebrows were raised after tea as Carey and Starc resisted the temptation of throwing the bat to ensure the match went through the motions. That's been a familiar sensation during this historic series.

Australia just kept batting as Carey, who had been somewhat under pressure due to patchy glove work and batting, effectively reverse-swept his way to his second Test half-century of his career.

An increasingly confident Carey powered to his highest score in what should be a tonic ahead of an important stint behind the stumps. While he capitalised on Australia's strong platform, middle-order batters Travis Head and Cameron Green missed out after being dismissed during a lively second session where the match appeared to be moving only for that to prove fool's gold after a laborious final session.

Pakistan toiled amid oppressive conditions in their Karachi fortress. They did attempt a fightback in the second session with spinners Sajid and Nauman Ali conjuring sharp turn on a pitch showing the first signs of encouragement for bowlers seven days into the series, the first between the teams in Pakistan since 1998.

Sajid bounced back with variations in pace and flight after notably struggling on day one where he pursued a defensive line of bowling before and after tea. The 28-year-old did a lot of heavy lifting and finished with 2 for 151 from 54 overs.

Shaheen Shah Afridi couldn't rouse the same energy he memorably produced during the tame draw in Rawalpindi apart from a lethal spell of reverse swing in the second session that was repeatedly thwarted by Khawaja's stout bat.

Pakistan's flagging bowlers were understandably weary by the time they took the third new ball, which only made scoring easier for Carey and Starc who finally started upping the ante.

In what felt like an eternity ago, Australia resumed day two at 251 for 3 and nightwatchman Nathan Lyon stole the show in the first hour with a breezy 38 to frustrate Pakistan's bowlers hoping for early inroads. But he fell short of a maiden Test half-century after being comprehensively bowled by Faheem Ashraf in Pakistan's only success in the morning session.

Lyon's unexpected cameo provided a rare source of entertainment in another hard grind of a day during this slow-moving series.