Australia won the toss in Karachi and opted to bat first.
Alongside Shaheen in the opening spell, Hasan Ali, who made his comeback into the Pakistan XI, was very accurate and troubled the batters with his tight outside off-stump line.
The openers continued to stay firm in the middle, as Khawaja also danced down the track to hit a six off Sajid in 17th over, followed by another six from Warner in the same over.
It looked like Khawaja and Warner would race to a century opening stand before Faheem Ashraf broke through to end the stand on 82.
Trying to get off the mark, Labuschagne attempted a risky single but a direct hit from Sajid found him short at the non-striker’s end.
Bowling tight lines and lengths, Shaheen and Ashraf didn’t allow the batters to score freely, keeping the run rate under control throughout the session.
The new ball didn’t really make much difference as Smith and Khawaja continued to keep the scoreboard ticking.