Siddikur shot an opening six-under-par 66 to lead the Indonesian Masters on Thursday but has world number two Lee Westwood trailing by two.

The man from Bangladesh fired two superb chip-ins in ideal scoring conditions to hold a one stroke lead from the chasing pack at Royale Jakarta Golf Club.

Thailand's Thongchai Jaidee with compatriot Prayad Marksaeng posted solid 67s to share second place with Singaporean Lam Chih Bing, Filipino Antonio Lascuna and Koreans Park Hyun-bin and Hwang Inn-choon in the US$750,000 showpiece.

Englishman Westwood, the hot favourite to win this week, was among seven players tied in eighth place on identical 68s. If he wins this week and Luke Donald does not in the United States, Westwood will regain his world number one spot from Martin Kaymer.

The Bangladeshi, who started from the 10th tee, said he was lucky to take the lead after holing out from 15 and 30 feet on holes 10 and two respectively.

"I was hitting and putting very well and it has been like this for a few weeks now. I'm getting more confidence every week and that's why I've been playing so well," said the 2010 Brunei Open winner.

Siddikur has come a long way since his days as a caddy at the Kurmitola Golf Club in Bangladesh where his first club was a broken seven iron head stuck on a metal rod.

He is the first Bangladeshi to play and win on the Asian Tour and has continued to shine with commendable performances. He finished in eighth place at the Maybank Malaysian Open last week and was placed second at the SAIL Open in India last month, losing only by one stroke to Kiradech Aphibarnrat of Thailand.

Despite his success in Asia, Siddikur admitted he was feeling nervous playing with world number two Westwood.

"I saw the draw yesterday and was feeling a bit excited playing with one of the best players in the world. I have to admit I felt a bit shaky this morning playing with him," he said.

Thongchai, a three-time Asian Tour Order of Merit champion, who played with Siddikur and Westwood turned in 30 highlighted by an eagle three on the 12th hole.

He was firmly in the lead before dropping a costly double bogey on the first hole.

"I was distracted by a camera and lost concentration from there on. I missed a lot of good putts on the back nine but made birdie on the last to put myself near the leader," said the decorated Thai, who found 15 greens today.

Lam was six-under through 12 holes but wobbled in his closing holes with one birdie against two bogeys.

"I haven't been playing that great this year but got off to a good start by hitting my shots close to the hole. That got me going and I started making a few putts. It seems like things aren't clicking in my game but I feel that I'm pretty close to returning to my best," said Lam, who has won once on the Asian Tour.

Westwood is determined of focusing on the Indonesian Masters and is unperturbed by the fact that he has a chance of regaining the world number one spot this week.

"I'll let things take its course and see what happens at the end of the week. Like I said before, I'm here to win a golf tournament," said Westwood, Europe's number one in 2000 and 2009.

He struggled to get his putter on fire early in the round but birdied his closing two holes to put himself two strokes from the lead.

"I played solidly but I was a bit frustrated out there. It has been the story for me so far, hitting it great from tee to green and giving myself a lot of chances but not taking it," added the Englishman.