Shane Warne believes the lack of cover for Nathan Lyon as Australia's Test spinner is a "real issue" and he has been disappointed with some states not selecting a frontline spinner in the early stages of the Sheffield Shield.

While Australia would not want to lose Steven Smith or Pat Cummins to injury, the loss of Lyon could be an even bigger headache given the gap that has developed between him and the rest of the options available around the country.

Australia did not select a second frontline spinner for the Ashes with Jon Holland, the Victoria left-arm bowler who was in the Australia A squad, not making the cut leaving Marnus Labuschagne's improving legspin as the next spin-bowling resource.

Labuschagne is a more-than-handy option for Tim Paine to have - as he showed with the ripping leg-break to remove Jack Leach late in the Old Trafford Test - but it would be a tall order for him to be thrust into a Test as the only spinner.

It is not a problem Australia have had to confront with Lyon's impressive durability meaning he has never missed a Test through injury during a 91-match career that has brought 363 wickets, but all it would take is a fielding mishap or blow in the nets to leave a significant problem.

Holland probably remains the next in line, but he was left out of Victoria's match against Western Australia in Perth, Ashton Agar might be a candidate while Queensland's Mitch Swepson was the second-highest wicket-taker among spinners last season but has yet to play this summer.

"Luckily we have such a quality spinner in Lyon, he's done so well in all conditions around the world, held that attack together, but if something happened to him it would be a real issue," Warne said at Fox Cricket's season launch. "It's important for Australia - I'm not saying Lyon is retiring or anything, he's got a lot more in him - that if something does happen for Australia that someone could set up."

Only four spinners other than Lyon took more than 10 wickets in the Sheffield Shield last season: South Australia's Tom Andrews (12 at 14.50), Steve O'Keefe (20 at 27.95), Swepson (24 at 38.16) and Holland (26 at 28.15). In the first two rounds of this season's tournament, just 18 wickets have fallen to spin. That, perhaps, is partly mitigated by there being two matches at the WACA and the Gabba but Warne said that room should be made for a frontline spinner regardless of conditions for the benefit of Australian cricket.

"They should always pick a spinner, it's disappointing if sides are not picking spinners regardless of conditions we should be encouraging spinners in all forms because they'll learn how to bowl in different conditions. The job of Sheffield Shield sides is to make sure you are producing international cricketers, it's not just looking after your own state. You have to make sure Australian cricket is strong and they should be picking spinners."

In terms of Australia's side for the opening Test against Pakistan next month, Warne endorsed bringing Usman Khawaja back to open alongside David Warner and introducing Will Pucovski at No. 6. "I think it's time we picked a good, young player in there, bit like the old Australian way. Put him in at No. 6 and he can work his way up," he said.