"I'm really happy I'm playing at such a high level with all the great players out there".
Sharma was solid on the front nine and recorded five birdies on the back nine.
Sharma earned his place in this week's field courtesy of two early season victories on the European Tour which has him leading the Race to Dubai but his step up in form in this class of field has been a revelation. "I couldn't be in a better situation".
Sharma, who opened with a 65, stood on 11-under par 131 with Spain's Sergio Garcia and Rafa Cabrera Bello and American Xander Schauffele sharing second on 133. He hopes to jump from 75th in the world rankings into the top 50 in time to qualify for next month's Masters, the year's first major championship. "Even after the rain (lightning) delay that we had, just to make birdie on the last hole (on nine), absolutely fantastic", said a delighted Sharma.
After his only bogeys at the second and third holes, Sharma had back-to-back birdies at the par-5 11th from 10 feet and the par-4 12th from 23 feet.
Garcia shot up the leaderboard late with a birdie on the par-four 10th, and an eagle on the par-five 11th and a birdie on 18.
"I played so well, and the bogeys that I made today were just three-putts". It's my first WGC and I was happy that I'll play four days because I missed the cut in the last two events that I played.
"When I came out on Monday I was so overawed by just so many people being here and so many kids coming up to me and asking for autographs", he told PGA Tour radio after his round.
With no cut, all 64 players in the field will play the weekend. "You have to expect great things from yourself if you want to play at a high stage".
Sharma blasted his opening tee shot two feet from the cup for a tap-in eagle.
Defending champion Johnson is four strokes off the pace at the halfway stage of the exclusive event, while three-time major victor Spieth is two shots further back.
"But I put in a lot of work to get my yardages dialled in and I think that's very important here. Obviously the final destination for me is the PGA TOUR, that's always been my dream", said Sharma.