Warner needs to prove fitness in Shield: Lehmann

David Warner has 15 days for his still broken left thumb to heal if he wants to be selected for the first Test against New Zealand.

Coach Darren Lehmann says the injured opener has to play the opening round of the Sheffield Shield in order to be picked for the Test at the Gabba, which starts on November 5.

X-rays on Friday revealed Warner's thumb to be still broken, four weeks after he was struck by a delivery from England's Steve Finn.

Warner will have another x-ray this coming Friday and is hoping to test out the injured digit in the nets for the first time on Monday, nine days before New South Wales' Shield match against South Australia gets underway on October 28.

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Both Lehmann and Warner are confident the vice-captain will be fit for the day-night game at Adelaide Oval, with the coach adding the match was an essential part of Warner's preparation for the NZ series.

"I'm pretty sure he'd have to play," Lehmann said. "If he's not going to play that he's probably not going to be fit enough (for the first Test).

"Again, we'll cross that bridge when we come to it but all signs are he's going to play."

Lehmann said playing just the one Shield match would be enough for Warner to prove he's ready for the first Test.

"For him, yeah. He's played a lot of cricket anyway," Lehmann said.

"You'd love him to have a bit more time but we're not too worried about it, especially with the way he plays."

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While confident he'll be available to take on the Redbacks, Warner believes he could still perform strongly in the first Test even if he was unable to take part in the Shield clash.

But he acknowledged that should he be unavailable for the Adelaide game, it would be up to selectors to decide if his preparation was adequate enough to play in the first Test.

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"I probably can, but I haven't spoken to selectors about that," he said.

"But my goal is to play that Shield game, I want to play that Shield game to have a hit because I don't think I'll be able to get out here and play any of the last couple of games for the Matador Cup.

"I think eight years on the road playing a lot of cricket, you don't lose that (ability) overnight.

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"I think this four to six week break mentally (has) freshened me up and I think it's going to put me in good stead for the summer.

"You're only one or two hits away in the nets, an hour off getting back to what you can do. But obviously batting against bowlers is going to be the key."

Warner showed off the damaged thumb at Australia's red-ball training camp at Hurstville today, with the digit covered by a protective guard in order to prevent any further damage.

The injury will stop him from taking any active part in the two-day camp, which has been scheduled to give Australia's players some much-needed practice against the red ball ahead of the Test summer.

Warner said he was more concerned about how his injured thumb would respond to fielding again rather than how it would affect his batting.

"I think it'll come down to when I have to catch a ball I'll be a little bit hesitant," he said. "But I've broken this before and I know exactly what I have to do. That's getting it right with the bat first and then we'll worry about the fielding and catching later."

Selectors will decide on Australia's squad for the first Test on October 29.