'You can't do that': Aussie umpire's 'embarrassing' act shocks cricket world

Umpire Greg Davidson caused uproar in the Big Bash on Sunday night when he changed his mind on an LBW decision halfway through raising his finger to signal a wicket.

Adelaide Strikers spinner Rashid Khan thought he had trapped Melbourne Renegades batsman Beau Webster in front, and Davidson began raising his index finger.

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But the umpire instead scratched his nose, sparking confusion amongst players and the 20,089-strong crowd.

Replays showed Rashid's delivery would have hit the wicket, however, it was Davidson's belief that the batsman had nicked the ball.

"It was one of those things, heat of the moment," Davidson told Channel 7 after the match.

"I started to think and then got a second noise through my head, so I decided to change the decision halfway through and gave it not out."

Webster finished unbeaten on 36 as his Renegades suffered an 18-run defeat, their fourth in succession to start the new season.

Both teams were quick to move on after the match.

Strikers opener Phil Salt dismissed it as a simple human error.

"I saw his hand start to go up and I didn't see the initial sort of moustache scratch," Salt said.

"When that came up on the big screen, I just cracked up (laughing).

"It happens, doesn't it? He's only human ... you can't get all of them right."

Renegades coach Michael Klinger couldn't recall seeing a similar incident in professional cricket, but praised Davidson's courage and quickthinking.

"To be honest, I like it," Klinger said.

"I think he felt he made half a mistake and he thought that Beau hit it.

"I think it's gutsy for him to change it halfway through, so I commend him for that.

"I actually think it's the right call whether it happened for us or against."

The incident immediately went viral around the world, with fans and commentators divided on social media about whether it was simply a funny mishap or an embarrassing look for the Big Bash.

Bizarre scenes at Marvel Stadium

Davidson's call wasn't the only issue that caused a stir amongst fans on social media, many of whom were quick to point out the unusually slow Marvel Stadium outfield.

Despite a good pitch for batting in the middle, both sides made their lowest totals of the season from their allotted 20 overs.

The Strikers finished with 6-155, with the Renegades posting 8-137 in response.

"It was slow. They've obviously had different (events) on here ... so there's reasons why," Klinger said.

"In previous years when we've played here it hasn't been this slow and there's been higher scoring.

"It would be nice if it could be a bit quicker, but at the end of the day it's the same for both teams, so it doesn't cause a difference in the game.

"But it's obviously a better spectacle if the outfield's a bit quicker."