Australia A 99 for 4 trail India A 107 (Doggett 6-15) by eight runs

Konstas, the 19-year-old who has been the most talked-about player this season, edged behind in the opening over against Mukesh Kumar as he looked to drive, and Bancroft, after four single-figure Sheffield Shield scores, was given caught down the leg side although replays showed it came off the thigh pad. Bancroft, who couldn't force his way back into the Test side last season despite prolific domestic form, threw his head back in frustration.

Harris reached double figures but was unconvincing. He survived a huge appeal for caught behind and was then dropped on 8 at third slip by Baba Indrajith against a ball that straightened from around the wicket from Kumar. After the let-off he managed a pleasing on-drive but gave his innings away when he flashed at Prasidh Krishna, who is part of India's Test squad, and was sharply taken at second slip. Prasidh could have had a third late in the day when Cooper Connolly was given a life in the cordon.

To add to the intrigue McSweeney, who bats three in the Sheffield Shield but is No. 4 here to accommodate the three openers above him, played as solidly as anyone all day, facing 110 balls for his 29, to give further credence to the talk that he may yet be the solution at the top of the order.

Speaking earlier in the day in Melbourne, Australia head coach Andrew McDonald admitted there was more uncertainty around selection than is ideal, but the final decision would not come down to a single innings.

"I think sometimes you're pushed into a space where you can't give certainty a long way out," he said. "There is a balance in that we prefer to be more settled coming for the summer, no doubt. If you have certainly that's fantastic, but there'll be moving parts in the summer as well that create discussions and decisions about who's going to play the next Test. Whilst we want to give clarity and certainty, sometimes that's not always able to happen.

"There's a lot of context and consideration around body of work for those senior players in Marcus Harris and Cameron Bancroft. Clearly Sam Konstas hasn't been able to have that body of work behind him because of the limited Shield cricket that he's played, and Nathan McSweeney is somewhere in the middle of that.

"You take Sam for example, he's had limited experience in Perth, and then obviously up to the Gabba, so there's incredible challenges for players who haven't played in those conditions before, but it's not to say that he can't do that either - he's a fast learner."

The tone for the bowler-dominated day was set in the second over when India A captain Ruturaj Gaikwad was brilliantly caught down the leg side first ball by Josh Philippe. Jordan Buckingham added a second in his first spell with a lovely delivery to find the edge of Abhimanyu Easwaran who is another in India's full Test group.

Sai Sudharsan made a promising start before edging behind against Doggett to begin what would be a memorable day for the South Australia quick who was only in the side as a second reserve having been called up to replace the injured Liam Hatcher, who in turn had replaced Mark Steketee.

Doggett hit the perfect full length on a surface offering the quicks encouragement and troubled all the batters. After offspinner Todd Murphy had removed Indrajith on the stroke of lunch - given caught at short leg when it was unclear if bat was involved - Doggett really got to work after the interval as he scythed through the middle order.

Ishan Kishan flashed an edge behind looking to counterattack and Devdutt Padikkal, who had provided the most resistance and was the day's top scorer with 36, edged an attempted drive to give Philippe his fifth catch. Doggett's fifth came when he trapped Manav Suthar with a yorker and a career-best sixth when he cleaned up Prasidh to leave India A 86 for 9. Navdeep Saini (23) managed to lift the total into three figures.