It's the $500 billion heavyweight bout between the country's big four banks - Westpac, ANZ, NAB and the Commonwealth Bank. The prize is control of Australia's fastest-growing superannuation sector - the self-managed super funds market.
Battling it out with the banks are the major wealth management groups and investment banks.
What was once seen as a major competitive threat for the big end of town - especially after the global financial crisis when many investors pulled their money out of funds in droves because they felt they could do a better job - has turned into key growth opportunity.
The stakes are high, with the SMSF sector projected to balloon to about $2.2 trillion over the next 25 years - roughly 35 per cent of what is forecast to be a $6.5 trillion retirement savings pool.
Michael Rice, chief executive of actuaries Rice Warner, says there has definitely been a step-up by the banks and wealth management groups in the SMSF sector.
"They are all quite active and even the ones that are not large in this area have all got strategies to get into it."
While the banks have always had "high touch points" within the SMSF market, through term deposits, online trading platforms and more recently property loans, their push over the past six to 12 months is the first co-ordinated and holistic attempt to have a crack at this highly fragmented market.
Partly driving this move, say industry observers, is the fact that financial advisers can't make commissions through corporate superannuation and life insurance any more because of the introduction of MySuper - a low-cost superannuation product. As such, financial advisers - mostly owned by the banks and AMP - have had to look at new areas where they can charge fees.
"Where there's lots of money, of course, lots of people want to play in that game and the banks and AMP, in particular, they want to share in it," Rice says.
In one corner of the ring, NAB is positioning itself as a financial services product provider, right across investment solutions, financial advice to life insurance, while ANZ wants to make its mark in digital technology and the self-directed space.
Last month, ANZ unveiled its first major assault into the sector, its new digital solution for SMSFs, which it believes will enable the bank to provide clients with an integrated digital product that helps them manage all their self-managed superannuation needs in one place.
Following a group-wide strategy review around Westpac's bicentenary in 2017, one of the senior management team identified that the bank needed to be better positioned in the SMSF sector. Not long after - some 18 months ago - an SMSF business unit was born, and a "more co-ordinated approach" was immediately taken across the group.
BT Financial Group's Chris Lumby, who heads up the SMSF unit, sees Westpac's role "helping customers make the most of their self-managed super fund", whether that's providing them with more educational content or making their life easier to manage their SMSF.
"It's very much around this help piece, as opposed to, outsource this to us."
He said Westpac had relationships with more than 100,000 SMSFs across the group today and was continuing to experience "good growth".
Meanwhile, AMP has been moving quickly to make its presence felt in administration services and financial advice.
Its acquisition of SMSF administrator Cavendish last year catapulted AMP into the largest professional administrator in the market, giving it a clear edge over its rivals.
On the financial advice front, AMP SMSF managing director Paul Sainsbury says so far this year, it had delivered "more than 28,000 hours of training to its advisers, accountants, independent financial advisers, as well as trustees around the management of self-managed superannuation. Mr Sainsbury says its research showed "SMSF investors often feel lonely after the initial set-up phase - so ongoing financial advice is becoming a more attractive proposition".
AMP estimates that of the 500,000 trusts in the market, it provides services to about 15,000 of them.
NAB has been making its own inroads as a financial services product provider. "What we are finding is that more and more SMSFs are coming to us [when] their SMSF is set up by their accountant. They have an administrator and they want to be able to access ... often in a self-directed way our key products," says NAB wealth solutions boss David Gall.
"We don't want to tell an SMSF how to deal with us, we are happy for them to choose how they want to deal with the organisation", whether that be through a financial planner, fully advised or in complete DIY capacity, he says.
One untapped market which he sees as a big growth opportunity for the NAB group is the refinance market.
But as competition in the SMSF market quickly steps up, one prominent finance expert who has concerns is Noel Whittaker.
Not mincing his words, Whittaker - the man behind Money's Ask Noel column - believes the big banks are encouraging people to open up self-managed super funds so they can on-sell products such as property lending so they can meet their loan budgets.
"SMSFs are not appropriate for most people," he says.
Whittaker believes SMSFs are only right for people who are great investors in shares or "if you are a small business person and you want to put your business premises in your super fund and be your own landlord, it's perfect for you". Another reason would be "if you want to invest in things like a property syndicate which is never going to be on the approved product list of any of the big banks because it would take too long to approve it, it would be perfect for you". He says they are the only reasons why people should open SMSFs.
SMSF Professionals' Association of Australia chief executive Andrea Slattery warns the banks against treating the sector as a "cash cow".
"If you want to play in this space," she says, "you need to enter it with three
things in mind. You need to provide value- added services, you need to provide efficient and effective services and you need to be competent."