Agarwal, thrusted into the squad following failure of KL Rahul and Murali Vijay, responded with a 76-run knock, sorting out India's opening woes to some extent.
Melbourne: Debutant Mayank Agarwal provided the base with a confident half century before Virat Kohli and Cheteshwar Pujara steered India to a solid 215/2 on day one of the third Test against Australia, here on Wednesday.
Agarwal, thrusted into the squad following failure of KL Rahul and Murali Vijay, responded with a 76-run knock, sorting out India's opening woes to some extent.
The conditions, though, were completely different from what Rahul and Vijay had countered in bowler-friendly Adelaide and Perth.
The Melbourne Cricket Ground (MCG) pitch turned out to be docile, ideal for someone making his Test debut as the Australian pacers had to bend their back to get the Kookaburra ball to rise sharply.
Make-shift opener Hanuma Vihari did not make many runs, getting just 8 off 68 balls in his 40-run stand with Agarwal but they batted out 18.5 overs, India's longest opening stand in terms of balls faced in Test cricket across Australia, New Zealand, England and South Africa since December 2010.
Virender Sehwag and Gautam Gambhir had batted out 29.3 overs against the Proteas at Centurion in that year.
The combination of Agarwal and Vihari was India's sixth opening pairing in 2018, and fifth in 11 overseas Tests this year.
Agarwal missed out on scoring a hundred on Test debut but grabbed the opportunity with both hands. His 78 came off 161 balls with eight shots to the fence and one over it.
During his knock, he became only the second Indian to make a 50-plus score on debut on Australian soil after Dattu Phadkar (51) at SCG in Dec 1947.
Overall, he became the seventh Indian batsman to score a half century on Test debut. He fell at stroke of tea, caught down the leg side to be second victim of paceman Pat Cummins, the only successful bowler for the hosts today.
Skipper Kohli and Pujara then took control over the proceedings denying the hosts any more success in the final session. However, Kohli survived a hostile Mitchell Starc over towards the end to stay unbeaten on 47. Tim Paine grassed a caught behind chance when Kohli chase one from Starc in that over.
Kohli and Pujara, who is batting on 68, have stitched together a 92-run stand for the third wicket.
The Indian captain had walked out to bat to a mixture of cheers and boos, but soon impressed the capacity crowd at the MCG with his repertoire of strokes. He sped off the blocks and at one stage was scoring at strike rate of 70-plus before Australia reined things in with some tight bowling.
It soon reflected in India's overall run-rate as well which didn't cross 2.5/over all day.
At the other end, Pujara continued in his usual manner and brought up his 21st Test half century off 152 balls.
Australia tried their best to etch out a breakthrough and in desperation also wasted a DRS review for lbw off Nathan Lyon (0/59).
They took the second new ball in the 83rd over, and the big moment came in the 87th over when Paine dropped Kohli (on 47) off Starc (0/32).
Earlier, Agarwal kept the scoreboard ticking after a watchful initial period, reaching his maiden Test half century off 95 balls.
It was only the second instance in 11 overseas Tests this year that Virat Kohli was yet to arrive at the crease with 100-plus runs on the scoreboard. The first instance was in Nottingham during the second innings against England.
To their credit Australia created chances in the latter half of the second session. In the 52nd over off Mitchell Marsh, a delivery looped up towards gully off Pujara but fell just short of a diving Usman Khawaja.
Then, three overs later, Agarwal edged Cummins through the vacant third slip. The pacer picked himself up though and three balls later he had Agarwal as Australia got a boost going into tea.
It showed in how Lyon came on to bowl as early as the eighth over, only the second time in his Test career that he had done so. Even in the previous four Indian innings on this tour so far, he had only come on to bowl in the 14th over each time.
Vihari took 25 balls and 33 minutes to score his first run as he batted with patience, which was lacking in previous opening partnerships in the first two Tests.
He was hit on the helmet in the 13th over off Cummins as Australia started bowling short and attacking the batsmen more. The makeshift-opener shrugged it off and went on to face 66 balls, the second highest for an Indian opener in five innings this series.
Cummins got him off a sharp rising delivery in the 19th over, as Vihari took his eyes off the ball and gloved it to Aaron Finch in the slip region. The Australian pacers continued to test the Indian batsmen with sharp bouncers at every opportunity possible.
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