'When you need to go, you need to go'

When you gotta go, you gotta go.

This was the simple explanation of Australia opener Matthew Renshaw, who had that nauseating feeling just moments before his opening partner David Warner was dismissed in the morning session of the first Test against India and was left with no choice but to retire ill and answer nature’s desperate call.

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Renshaw, on 36 with around 15 minutes before the lunch break in Pune, left the field when Warner was dismissed, much to the confusion of his incoming skipper Steve Smith, television broadcasters and the buzzing crowd.

"It came pretty suddenly,” Renshaw said after play on Thursday.

"Maybe five or 10 minutes before Davey (Warner) got out I asked Richard (Kettleborough, standing umpire) how long there was till lunch and he gave me the answer of 'half an hour' and I was struggling a bit then.

"It wasn’t an ideal situation to be in."

With no visible injury to the 20-year-old, commentators and media were dumbstruck as to why the batsman left the field before word came through that an upset stomach had forced him to retire ill.

After getting the all clear from umpire Kettleborough that he could retire and later return, Renshaw then had to explain, in haste, to Smith the bleak situation he was facing that required immediate attention.

"He (Smith) wasn’t too thrilled about it but he understands that when you need to go to the toilet, you’ve got to go to the toilet,” Renshaw said.

"It wasn’t an ideal scenario but it’s life, pretty much.

"Obviously we just lost a wicket so there would be two new batsmen out there but it’s a hard scenario to be in and he understood.

"We’ve had a chat now and we’re all good."

The Queenslander returned two-and-a-half hours later to resume in his innings at the loss of Peter Handscomb and batted another 90 minutes before he was dismissed for 68 in his subcontinent debut.

"I wasn’t too sure on the ruling," he explained.

"I didn’t know you could retire ill so I thought I just had to get out there and make sure I batted until lunch.

"Then coming back it was probably a bit strange for me waiting to bat because as an opener you just go straight out there and bat.

"That was probably the most challenging bit, waiting to bat.

"I felt quite bad knowing that I could be letting the team down, so that’s why I went back out there.

"I wanted to do my bit for the team and try and make sure we had a good day."

Former Australia captain Allan Border had questioned Renshaw’s decision to leave the field, quipping on Fox Sports that the 20-year-old would have to be "laying on the table in there half dead" having exposed two new batsmen just before lunch.

But Renshaw was content that Smith understood what was happening and the urgency of the situation.

India batting coach Sanjay Bangar was philosophical when asked about Renshaw’s unfortunate illness and praised the left-hander’s performance on challenging day one at the Maharashtra Cricket Association Stadium.

"When you have to answer the nature’s call, no amount of will power and mind power can control that,” Bangar said.

"He had to go, he held back, he was having that conversation with Steven Smith whether he would do it or not.

"Such instances definitely happen. It all adds to the colour of Test cricket.

"Credit to him, he came back, he started really well and applied himself and showed a lot of character.

"For a younger player he showed a lot of character playing in his first Test in India."