Virat Kohli's conduct came under the microscope in the Boxing Day Test in Melbourne on Thursday after a clash of shoulders with teen debutant Sam Konstas but the incident did little to knock the Australian wonder boy off his stride.

With Konstas well on top of India's bowlers on day one, Kohli was booed by the crowd at the Melbourne Cricket Ground after bumping into the 19-year-old as he walked down the pitch for a chat with opening partner Usman Khawaja at the end of the 10th over.

Kohli and Konstas turned to face each other and exchanged words, prompting umpire Michael Gough and Khawaja to step in to defuse the moment.

Former Australia captain Ricky Ponting, who was covering the game for host broadcaster Seven Network, said veteran batsman Kohli was clearly the offender.

"That man (Kohli) might have a few questions to answer," Ponting said.

"When you're out there batting, the batsman owns the wicket. The crease is his. Especially between overs like that."

Former England captain Michael Vaughan also put the blame on 36-year-old Kohli.

"Virat Kohli is such an experienced pro, being wound up by a 19 (year old)," the Fox Cricket pundit said.

"It's Virat that walks into Sam."

Konstas, who replaced the dropped Nathan McSweeney in the side, appeared unruffled by the clash, smashing Jasprit Bumrah for four on the next delivery and hitting a six over the Indian pace spearhead's head on the way to 18 runs from the over.

Konstas downplayed the incident after Australia went to stumps at 311 for six.

"I think he accidentally bumped me, but I think that's just cricket, just the tension," he told reporters.

The International Cricket Council (ICC) bans "inappropriate physical contact" and those found guilty can be suspended for matches if the offence is deemed serious enough.

Indian media reported Kohli had accepted a 20% cut to his match fee and one demerit point, leaving him free to play the fifth and final Test in Sydney.

The ICC has not publicly confirmed the sanction.

India assistant coach Abhishek Nayar told reporters he had not seen the incident and that emotions were natural in a big game.

"But I'm pretty sure that it's not as big as it seems," he said.

Batting maestro Kohli had shrugged off a dire run of form with a century in the series-opener in Perth but has managed just 21 runs in three innings since in the series.

With the temperature surging past 30 degrees Celsius (86°F)in the morning, his mood may not have been helped by Konstas surviving a nick off Bumrah that fell just short of him in the slips.

Kohli had earlier laughed openly at Konstas when the teenager botched two attempts to scoop Bumrah behind the wicket.

Konstas succeeded on his next three efforts with the T20-style shot, scoring boundaries on each.

Konstas was eventually dismissed for 60 off 65 balls when trapped lbw by Ravindra Jadeja before lunch.