New-year headaches for Australia

Marcus Harris has made a decent fist of his introduction to Test cricket against a very fine attack. Aaron Finch's position at the top looks much more vulnerable, though there were hints from Langer that he may retain the role for the New Year Test. But he is a middle-order red-ball batsman trying to be manufactured into an opening batsman. His series tally is 97 runs, with more than half coming in one knock in Perth. His second-innings dismissal at Melbourne, guiding the ball one-day style to slip, was of particular concern. However, rather than ditch him all together it could be fairer to give him a crack lower down the order if there is the belief he is currently one of the best six batsmen in the country. In the short-term - for Sydney at least - that would mean Usman Khawaja opening, a position from where he has two of his seven Test hundreds, but that would have knock-on effects.

Khawaja is currently Australia's best batsman and in 33 off his 38 Tests has been at No. 3 (it would have been 34 but for the last-minute promotion against South Africain Adelaide when he then made 145). With talk that Khawaja should open, there is the debate about how different that role is to being first drop - after all, a batsman can be in after one ball. But if that happens it means someone else being shoe-horned in at No.3. It would have to be Shaun Marsh (average 25.66 in that position) or Travis Head, Australia's leading run-scorer in the series but still raw at Test level and with dubious shot selection. There could be a danger of Australia weakening the one bit of relative strength they have in the top order.

The aforementioned Head has shown some promise, firstly in the UAE and then with two half-centuries in this series, and has soaked up the second-highest number of deliveries (498) against India. However, his last four dismissals have involved being caught at third man twice and bowled twice trying to attack the India quicks. Shaun Marsh might have had cause to leave Melbourne feeling a touch aggrieved - defeated by a wonderful slower ball from Jasprit Bumrah then given lbw to one marginally clipping leg stump - but has to deliver more as a senior player. Peter Handscomb was dropped for Melbourne, then went away and smashed some BBL runs. Tim Paine offered him encouragement for Sydney on the basis of his skill against spin but the man himself wasn't expecting a swift return. Mitchell Marsh (more on him in a moment) had a horror match with the bat at the MCG and there has been the suggestion that Paine should elevate himself.

Australia's quicks would have been well and truly cooked in Melbourne without Mitchell Marsh's 26 tight overs. But he is picked as an allrounder and his batting returns have slumped: an average of 7.50 in his last five outings. For someone touted as a good player of spin by Langer before the third Test, he played two horrendous shots against Ravindra Jadeja. He looks especially vulnerable after the call-up for Marnus Labuschagne, who is seen as someone capable of being that fifth bowler after claiming seven wickets at 22 with his legspin in the UAE. Five wickets at 59.60 in the Sheffield Shield doesn't instill confidence but he would offer relief for the quicks and some support for Nathan Lyon. He was the last batsman left in the nets having a hit at optional training on New Year's Day and then did some extra bowling alongside spin-bowling coach Sridharan Sriram when everyone else had left. Steve Waugh, in a hand-written note posted on Instagram, selected both Marsh and Labuschagne in his XI with Finch dropped and Shaun Marsh to open. His hashtag #marshtoplaygilchristrole might raise a few eyebrows, but it highlights the difficulty Australia find themselves in.