'There's a gap': Greats baffled as Cummins dudded

Pat Cummins may have been the victim of a phantom snick, given out caught behind on the fourth morning of the Boxing Day Test against Pakistan despite replays suggesting he missed the ball.

A faint sound meant umpire Michael Gough initially gave Cummins out off the bowling of Aamir Jamal for 16 in the 77th over of Australia's second innings.

Cummins immediately reviewed the decision, and the replays showed a small spike on snicko, although there appeared to be a gap between bat and ball, suggesting the noise came from elsewhere.

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To further murky Gough's decision, hotspot showed no mark on the inside edge of Cummins' bat.

But third umpire Richard Illingworth instructed Gough to stick with his decision, and Cummins trudged back to the pavilion.

"I'm not sure how you can give that out," Former English fast bowler Isa Guha said in commentary on Fox Sports.

"It was given out on-field, there is a little spike as it goes past, but you can clearly see there was daylight between bat and ball.

"The glimmer (on snicko) is a noise, (but) that could be anything."

England great Michael Vaughan agreed it was dubious at best.

"It looked like there was a gap between the ball and the bat," Vaughan said.

"The glimmer with the ball passing the bat isn't quite synched. There's a gap between the ball and the bat which is a concern for me, it looks like there is a bit of fresh air.

"But there was definitely a little bit of noise, although only slight."

The panel agreed if the decision had been given not out, there probably wasn't enough evidence for that decision to have been overturned and given out.

Adam Gilchrist pointed out the decision review system (DRS) was introduced to remove the "howler" from the game, and suggested the slight sound meant it probably wasn't a howler from Gough.

"Richard Illingworth had to give it out, because he needs evidence, and there was evidence so he had to give it out," Ian Smith said.

"There was also some evidence to say no, but he was governed by the bloke who said yes."

Cummins was the eighth Australian wicket to fall. Alex Carey, Nathan Lyon and Josh Hazlewood combined to put on 25 for the final two Australian wickets.