Bancroft, playing in his first Test match, showed the flinty side of his character when he took a direct throwback from bowler Jimmy Anderson near his groin without flinching.
Australia's David Warner plays a shot against England during their Ashes cricket test in Brisbane, Australia, Sunday, Nov. 26, 2017.
The ECB said there was no report of any incident from the venue, security or police and no injury reported.
Australian debutant Cameron Bancroft has words with Englishman Jonny Bairstow on day four of the first Ashes test.
This latest blow to England's campaign also revives memories of the infamous Walkabout incident in which Australian vice-captain David Warner was suspended for two Test matches prior to the 2013 Ashes series.
The behaviour of England cricketers has come under scrutiny after Ben Stokes was left out of the Ashes tour after he and Alex Hales were arrested following an altercation outside a Bristol nightclub in September and released under police investigation.
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European Central Bank chief Andrew Strauss was spotted looking dejected late on Sunday in Brisbane after Bairstow was questioned about the matter.
England now find themselves bracing to go down 1-0 and with a huge cloud of controversy hanging over one of their most important players. Bairstow scored 42 as England were dismissed for 195, leaving Australia 170 runs to win the Test and they ended the day - the fourth - only 56 adrift with all 10 second-innings wickets in hand.
The episode - where Bairstow allegedly head-butted Bancroft - took place at a hotel when England were in town for their first tour match, a one-day affair against a Western Australian XI on November 4. I'm all for it.
"We felt we had them under pressure at the time", Ali said of his partnership with Bairstow.
An ECB spokesperson declined to comment.
However, England are now facing a full-blown disciplinary crisis.
It is understood there was no involvement from any other players and Bairstow has since apologised to Bancroft. However, he has since gone on to make his Test debut, and has involved himself in quite a duel with the England keeper.