Paul Dunne's mission to make the Masters fizzled out in Mexico after a second-round four-over-par 75 left him six-over at the WGC-Mexico Championship.

A win or runner-up finish for the 25-year-old Greystones man would have pushed him into the the world's top 50 and sealed a spot at Augusta in April.

However Dunne followed up his opening 73 with another tough round, carding five bogeys and a double bogey on the par-four 12th to leave him 17 shots off leader Shubhankar Sharma.

The 21-year-old Indian's remarkable rise continued to gather pace as he claimed a two-shot halfway lead at Chapultepec Golf Club.

Sharma was outside the world's top 450 when he won the Joburg Open in December, and he followed that up with victory in Malaysia last month.

Those wins have put him top of the European Tour's Race to Dubai, while he has also risen to 75th in the official world golf ranking.

Making his World Golf Championships debut, Sharma opened with a round of 65 on Thursday and stormed home in 31 to follow up with a five under par 66.

At 11 under for the week Sharma leads by two from Spaniards Rafa Cabrera Bello and Sergio Garcia, as well as American Xander Schauffele.

"I'm really happy," Sharma said in quotes reported on the European Tour website. "I couldn't be in a better situation.

"I played so well, and the bogeys that I made today were just three-putts. Otherwise I just get the ball in play all day and it was great to finish with three birdies in a row.

"I thought about nothing, I just wanted to have fun. 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. Even though I missed the cuts, I knew I was playing well. So I just wanted to have fun, and yeah, I've had a lot of fun.

"I worked all my life to come and play at a high stage like this. You have to expect great things from yourself if you want to play at a high stage."