The 21-year-old, twice a winner on the European Tour this year, signed for an 8-under 64 at the controversial Gary Player designed DLF Golf Club to move to outright second in his home Open.
Sharma shot to prominence with a dazzling display at the WGC event in Mexico last week where he led through 54 holes before being overtaken Sunday by Phil Mickelson.
That performance captured the attention of the golf world and while second round play was suspended due to darkness with nine players remaining on course Sharma is the talk of the tournament.
"I can’t believe he’s only 21,” said playing partner Andrew ‘Beef’ Johnston. “The head on him is amazing, and his attitude.
"He’s come back from whatever score he was on, three or four over, to that. It’s incredible, so hats off to him. Very impressive."
NEW COURSE RECORDMarch 9, 2018
For the record, Sharma was 5-over after three bogeys and a double in his first nine holes of the tournament. He is 12-under for the 27 holes since, including his nine birdie-one bogey effort on day two.
"Today’s round will definitely rank up there as one of my most significant achievements, especially when it is played at this course," Sharma said after signing his card.
“"This is a tough course and it is not easy to go low here. I’m very happy with the way I played. I've shot a few low numbers in my career and this one is right in my top five.
"If you told me I would be seven under par going into the weekend after being five over par on my opening nine holes yesterday, I would just have laughed.
“To be able to bounce back is really important, I knew I was playing well and I had to push myself a little."
Grillo, who equaled the course record Thursday with a 65, continued to impress with a second round 68 to move to 11-under and four clear of Sharma.
The PGA Tour star has posted just two bogeys through the opening 36 holes, a rare achievement at one of the most difficult and quirky courses the European Tour visits all year.
The 25-year-old said he was somewhat surprised by his own scoring though keen to maintain the momentum for the weekend.
"When I practised on Tuesday and played the pro-am on Wednesday, I was telling myself that I’ll be in a good position if I can just shoot under par every day,” he said.
"Hopefully, I can keep my form going. I’ve done well over the past two days and I can’t ask for more. Today, I hit some bad putts, but I think I’ll be fine."
Terry Pilkadaris was the leading Australian after the opening round but is finding the going tough on day two at 8-over through 15 holes.
The New Zealand Open runner-up is one of the nine players who are yet to complete their second rounds but has a chance to make the cut when play resumes at 7am local time.
At 5-over with three holes to play he will need at least one birdie to join Wade Ormsby, Jason Scrivener, Marcus Fraser and David Gleeson for the weekend.
Ormsby is the best placed of the Australian contingent at 1-under and T25 while Gleeson is two shots further back and T35.
Fraser is 2-over and Scrivener 3-over while Jason Norris, Scott Hend and Andrew Dodt are all assured of having the weekend off.
SIGNATURE HOLES - 5TH AT SOUTHERN GOLF CLUB:
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