"He's obviously just got an upset stomach to some degree."
Renshaw shouldered arms when told about the comments of Border, who famously told a sick Dean Jones he was a "weak Victorian" because he wanted to stop batting during the 1986 tied Test in Chennai.
"That's just something I guess he grew up with, and that was his sort of mentality," Renshaw said.
"But Steve was good and he understand when you need to go to the toilet, you have to go to the toilet.
"He didn't really understand what was going on at the start, I sort of just ran past him .. he called me back and he wanted to have a discussion with me but I just told him I had to go off.
"He wasn't too thrilled ... but we've had a chat now, we're all good."
Renshaw returned to the crease and top-scored with 68.
Renshaw scuttled off after David Warner was dismissed, leaving two new batsmen at the crease.
Border claimed Renshaw wouldn't have even "thought about" coming off if Warner didn't chop a wide ball from Umesh Yadav onto his stumps.
"He probably thought he had time to race off the ground and get back on while the new batsman was coming out to the crease," Border said.
"If Shaun Marsh was dismissed in those last 15 minutes, I would've been ropeable as captain."
Border was filthy in 1986, when Jones was 202 not out at tea and didn't want to go out and bat.
Jones, who was urinating involuntarily and vomiting in extreme heat, went on to score 210 and was later put on a saline drip.
Renshaw, having never set foot in India before arriving last week, thoroughly impressed with the bat prior to his bathroom break.
The 20-year-old's defence was solid but he also stroked 11 boundaries, including a booming six off left-arm spinner Ravindra Jadeja.
AUSTRALIA V INDIA, 1ST TEST AT A GLANCE
STATE OF PLAY - Australia 9-256 at stumps on day one after winning the toss
MAN OF DAY - Matt Renshaw. Handled India's star spinners with aplomb despite his inexperience, the dry deck and a stomach bug that forced him to retire hurt.
KEY STAT - The 20-year-old Renshaw became the youngest Australian to post a Test half-century in India. Rick Darling previously held the title, having done it at age 22 in 1979.
KEY MOMENT - Mitchell Starc raised his bat after reaching 50 in 47 balls. Australia had slipped to 9-205 before Starc teed off.
BEST QUOTE - "(Steve Smith) wasn't too thrilled about (going off) but he understands when you need to go to the toilet you've got to go to the toilet," RENSHAW on the captain's reaction to him retiring hurt.
