India will host Australia in their spin-friendly backyard over four highly anticipated Tests starting Thursday, with Steve Smith saying winning the crunch series would be "bigger than the Ashes".

Australia have struggled to overcome conditions in India, with their last series win there coming in 2004 while their opponents have claimed the past three encounters, including twice down under.

Smith admitted that India is "a difficult place to win a Test match, let alone a series."

"If we are able to topple that mountain, that would be huge. I think if we can win in India, that would be bigger than an Ashes series," he said ahead of the first Test in Nagpur.

The visitors are reeling from a spate of injuries -- including to key pace-bowlers Mitchell Starc and Josh Hazlewood -- while the hosts are at near full strength.

Ravindra Jadeja has returned from injury to spearhead the spin department alongside Ravichandran Ashwin while star batter Virat Kohli is back in imperious form.

Australian captain Pat Cummins, who will lead his side's pace attack, said fast bowling could play a big part on India's notoriously spin-friendly wickets.

"I think, coming here to India, a lot of the talk is around big spinning wickets, mainly fast (-moving) Test matches, but it's not always the case," said Cummins.

"You need to get into the grind at times, and that role as a fast bowler might be bowling plenty of overs for not a heap of reward but doing a job for the team."

With Starc out for the first Test and Hazlewood and all-rounder Cameron Green in doubt for the entire series, Scott Boland, playing in his first overseas Test, will be called upon to open the bowling alongside Cummins.

Nathan Lyon, who has claimed 34 wickets in seven Tests on Indian soil, will lead the spin charge.

But the key battles for Cummins' side could be with the bat.

Smith was imperious during the last tour of India, scoring three centuries including a brilliant 178 in Ranchi. But opener David Warner struggled, crossing 50 on just one occasion as Australia lost the series 2-1.

On this occasion, Warner will open alongside Usman Khawaja, whose comfort against the turning ball and rich-vein of form could prove crucial.

Australia will look to Khawaja and top-order stalwarts Smith, Warner and Marnus Labuschagne to maintain their strong form and nullify India's bowlers.

- Jadeja 'blessed' -

A draw in any of the four Tests will be enough to secure world number one Australia a place in the ICC World Test Championship final at The Oval in June.

Second-placed India, led by Rohit Sharma, need to win at least 3-0 to assure themselves of a spot for the second time running.

Jadeja, a left-arm spinner and an attacking lower-order batsman, said he felt "blessed" after returning from his career-threatening knee injury.

"(I am) very excited and (it) feels really great that after more than five months, I am wearing an Indian jersey," Jadeja told bcci.tv.

Jadeja has a knack of picking wickets on Indian turners and along with Ashwin and most likely Axar Patel will form a lethal spin trio.

Star batsman Kohli has scored three one-day international centuries in his past four innings to overcome an extended batting slump and will be desperate for a first Test ton since November 2019.

Opener Shubman Gill -- nicknamed the "Smoothman" -- lit up the recent New Zealand series and Twenty20 sensation Suryakumar Yadav could get a place in the team with Shreyas Iyer out injured.

But coach Rahul Dravid knows that Australia will still be a tough challenge -- and says India have been practising their fielding skills as much as anything else.

"There's a lot of emphasis on close-in catching, slip fielding, things like that when you are on the road all the time and don't get time to build and work on those things," Dravid said.