India vs Australia: Virat Kohli 'irreplaceable' for India, says Allan Border

India captain Virat Kohli's decision to take paternity leave will give Australia a key advantage in the upcoming Test series, according to former Australian skipper Allan Border.

Kohli will leave the tour after the first of four Tests, due to start in Adelaide on 17 December, for the birth of his first child with Bollywood actress Anushka Sharma.

"I think that is a big 'out' for India," Border told The Times of India newspaper.

"He is irreplaceable at the moment as a batsman and as a leader," he added.

India are also scheduled to play three one-day internationals and three Twenty20 matches before the Border-Gavaskar Trophy Test series.

Kohli led India to their first Test series win in Australia on their last tour in 2018-19. But the home side were without batting stars Steve Smith and David Warner, who were serving one-year bans for ball-tampering.

Border said he was "very confident" of Australia's chances this time around, predicting a 2-1 win thanks to their quality bowling attack and batting line-up strengthened by Smith and Warner.

He said India could also struggle with the mental fatigue of spending weeks in "bubble" conditions so far from home. But he said the biggest factor would be Kohli's absence.

"I love the way he plays his game - he wears his heart on his sleeve," Border said. "I like his aggression and passion for the game. India as a team will miss that."