The 20-year-old, whose innings helped Australia to a dominant 365-3 in the third test against Pakistan, was largely a spectator in the morning as his opening partner David Warner scored a 78-ball century in the first session.
"That first session was something of a whirlwind, Davy was just absolutely smoking them and I was on not many," said Renshaw, who had notched up 25 runs by the lunchbreak.
"He keeps telling me I'm not going to keep up with him and I didn't try today."
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Warner's century was the first in the opening session of a test match on Australian soil but for his country's long-term cricketing future, Renshaw's initially more cautious knock was perhaps more important.
Brought into the side after Australia were humbled by South Africa in November, Renshaw confirmed he had the aptitude for opening at the highest level, even if he was surprised at quite how well he had done.
"You go into every game trying to do the best you can but I probably wasn't expecting to be this score tonight," he confessed.
He also showed no little courage to get back up after being knocked to the ground by a nasty blow to his helmet from a Mohammad Amir bouncer, an injury that required an examination by the team doctor under the new concussion protocols.
"He asked me if I was okay and I said I was fine. I just wanted to be out there, I didn't want to retire hurt on 91," Renshaw said, with the helmet and its misshapen grille in front of him on the table.
"He asked me the score and who was the last person out and how it was, I got them pretty right. I was four runs off the score so not so bad."
Renshaw has also clearly been on the receiving end of some good-natured teasing from the senior test players.
Vice captain Warner referred to him almost exclusively as "the youngster" in his news conference and suggested reporters ask Renshaw why Nathan Lyon had nicknamed him 'turtle'.
"I was coming out of my shell a little bit the first week (in the test squad) and then Dave Warner and Steve Smith came back and I didn't say too much," Renshaw explained.
"I've tried to embrace the turtle, the turtle and the bull they call Davy and me apparently."
(Editing by Amlan Chakraborty)
