'Never do that': Usman Khawaja under fire over baffling act

Aussie cricketer Usman Khawaja is coming under scrutiny for a bizarre decision to keep his helmet on in the outfield, after dropping a crucial catch late on day five of the dramatic drawn Test with Pakistan in Karachi.

Babar Azam's batting brilliance, combined with some fielding flops thwarted the Aussies as Mohammad Rizwan's late century helped Pakistan hold on for a draw.

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The series remains 0-0 ahead of the third and final Test in Lahore starting on Monday, although the Aussies will be kicking themselves about a series of missed chances that cruelled their chances of winning the second Test.

Vice-captain Steve Smith copped some brutal backlash on Pakistan Cricket's official Twitter channel after dropping three good catching chances on day four.

Similar opportunities went begging for the Aussies on day five as Travis Head and Marnus Labuschagne both spilled tough catches in consecutive balls, while fielding in close off the bowling of leg-spinner Mitchell Swepson.

However, the most straightforward chance fell to Khawaja with little more than three overs remaining in the Test and the Aussies needing just four wickets for victory.

Khawaja had been fielding in close as Aussie spinners Swepson and Nathan Lyon toiled away in search of the crucial breakthrough.

However, the Aussie batter - who has been superb this series with scores of 97, 160 and 44 not out - opted not to remove his helmet when skipper Pat Cummins sent him further back to take up a position at short cover when Swepson was bowling at Pakistan's Rizwan.

The Pakistani batter - looking set on 91 runs at the time - chipped a delivery straight to Khawaja, with the Aussie inexplicably putting the regulation chance down.

“The Australians in absolute disbelief. What a twist that would have been,” Simon Katich said in commentary.

If Khawaja had been able to hang onto the catch, the Aussies would have been licking their lips at the prospect of bowling to two tail-enders, rather than a man approaching a second innings century.

Usman Khawaja quizzed on decision to leave helmet on

Cricket commentator and podcaster Adam Collins lamented what could have been a game-changing moment, and whether Khawaja's decision not to remove his helmet - while fielding in a position where it's uncommon to wear one - ultimately proved costly.

“I think it is worthy to be critical of Khawaja still wearing his helmet at cover,” Collins said on his Final Word podcast with Geoff Lemon.

“He didn't need to be wearing his lid.

“Khawaja keeps the lid on and drops back to about… four or five pitches over — a position where you would never wear a helmet, right.

“I know it’s a small thing to nitpick on — he was so good throughout the Test... but had he had his time again he wouldn’t have a helmet on fielding where he was. Because that’s something you’re not ordinarily doing, taking a catch like that in that way, with a lid on.

“Maybe it wouldn’t have made a difference, but maybe it would have.

“That would have changed the Test match, I think, because they would have been eight (wickets) down at that point with a number of overs left. That would have been a different dynamic bowling to Hasan Ali than it would have been (with) Rizwan at one end and a fairly solid Nauman Ali (at the other).”

Collins' view was shared by plenty of other cricket fans on social media.

Pat Cummins defends Aussie tactics

Despite the disappointment of not getting the win, Aussie skipper Cummins defended his side's tactics after coming in for criticism for batting too long in their first innings and then not enforcing the follow-on after rolling Pakistan for 148 in their first innings.

"Coming over here in these conditions, at the start of the series if you had said it's going to be nil-all after two games, we would probably take that," Cummins said.

Australia's first innings stretched into day three before Cummins declared at 9-566 from 189 overs.

After skittling Pakistan for 148 all out in 53 overs, Cummins then opted not to enforce the follow-on.

Australia then extended their second innings some 35 minutes into day four when, overnight, they already held a 489-run lead.

Those 35 minutes could have been vital on day five as Pakistan negotiated 171.4 overs in making 7-443 to force a draw.

"In terms of the tactics, I think overall I wouldn't change too much, to be honest," Cummins said.

"Batting into day three gave us that chance to really have a crack at them on day three - it probably went better than we expected.

"But over here the wickets are pretty good. We carved up two and a half days of the best time on the wicket hoping that it was going to break up on day four and five."

with AAP

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