Rookie Australian opener Jake Weatherald is under mounting pressure to retain his spot at the top of the order after yet another disappointing Ashes dismissal.

The aggressive left-hander has struggled in his first Test summer, managing just 21 off 36 balls on Monday before being trapped lbw by Ben Stokes.

It marked the fourth time Weatherald had been dismissed in a similar fashion, as question marks grow surrounding his technique.

"There is a lot of work for Jake Weatherald to do," former England captain Michael Vaughan said on Fox Cricket after his dismissal on day two at the SCG.

"You look at that head position, and he is always falling over to the offside. It's exactly what England have been targeting all series.

"When you've got a real genuine weakness, which he looks to have with that head falling over, at this level … they're always going to be able to expose it."

Weatherald has now scored 167 total runs across the five Test matches, es and 72 of them came in the same innings at the Gabba in one knock.

Since that innings, the 31-year-old has continued to come unstuck, and there are now genuine concerns over whether he can maintain his spot in the Test arena.

There will be one more chance to impress in the second innings at the SCG, but if he fails to fire once again, Weatherald could be on the chopping block.

Aussie great Mark Waugh conceded it could be do-or-die time for the Darwin product.

"He needs to make runs in the second innings," he said on Fox Cricket.

"He seems to have lost a bit of confidence. At this stage, he hasn't convinced me he's a long-term Test player ... but if he's got runs in the second innings, fair play to him."

There are multiple options for Australia to choose from at the top of the order when the next Test series against Bangladesh comes around in August.

Matt Renshaw is gaining plenty of support from ex-players, while young guns Campbell Kellaway and Sam Konstas could be blooded with an eye towards the future. 

Konstas made 60 on his Test debut last s,ummer but after a tricky year, was left out of the squad for the Ashes and had a mixed first half of his Sheffield Shield campaign.

Kellaway is turning heads, scoring centuries for both Australia A and Victoria this summer, pushing his first-class average into the mid-30s.

The other opening position is likely to be retained by Travis Head moving forward, especially following the confirmation of Usman Khawaja's retirement.

Head has scored two centuries in the Ashes and looks poised for a third, finishing unbeaten on 91 at the end of day two in Sydney.