The 22-year-old Tran has contemplated quitting touring life after a lack of success on the Asian Tour but two impressive rounds at the Kota Permai Golf and Country Club may just delay his decision.
After returning in the morning to finish three holes of his weather-disrupted opening round, Tran brilliantly shot five birdies against a lone bogey to grab the joint lead on nine-under-par 135. It left him on the verge of making history as no Vietnamese player has won on the Asian Tour.
However, Thaworn, a 13-time winner on the region's elite circuit, will stand firmly in Tran's way. The 45-year-old Thai birdied his last hole for a 69 as he maintained his chase for an unprecedented 14th title in the RM1.2 million event.
Australian Marcus Both, who finished fifth here last year, is a stroke back following a 69 while Spanish rookie Javi Colomo fired a 69 as well which included an eagle on the par four 11th hole for equal fourth place with Filipino Jhonnel Ababa.
Ababa stands on seven-under for the tournament with one hole remaining after play was suspended due to darkness. He is the only player who did not complete the second round and will return at 7.50am on Friday to finish his last hole. The third round is expected to start before 8.50am.
Tran, who has not registered a top-10 in three seasons on the Asian Tour, was delighted to feature atop the leaderboard with one of Asia's greatest players. "I'm just having a walk in the park," he said.
"I'm not thinking about anything which I've managed to do in the last 36 holes. It won't be easy to do that in the last two rounds though. But that's the game of golf, you need a bit of nerves to push you forward.
"I was planning to do some teaching and my family has some business too. That's just a plan because you never know what might happen in the next four months or this week. I'm trying not to think about it.
"I didn't play golf for six weeks after the Queen's Cup [in June]. I didn't even touch my golf clubs and golf seems like a game to me now rather than before when I treated it like a job."
Thaworn didn't produce his A-game, dropping a double bogey on 13 after flying the green with a wedge shot but he hit an exquisite approach to four feet on 18 to ensure his presence alongside Tran. "I didn't hit it good. I think I didn't have the power today [Thursday], so this is a good score. Just felt a bit tired," he said.
"However, I'm feeling good about my chances. I know Michael as he plays on the Thai tour. He is a long hitter and he has won one tournament, beat me and Prayad (Marksaeng). He's playing well this week."
After playing 21 holes on Thursday, Both was disappointed that he made three "soft" bogeys on holes eight, 14 and 16 but believes he has an advantage at Kota Permai.
"This is the sort of golf course which I like. You don't have to overpower it but just position the ball around here. That's sort of my strength," said Both, who is a two-time Asian Tour champion.
The halfway cut will be set at 144 with two Malaysian amateurs Abel Tham, who shot a hole-in-one in his round, and Low Khai Jei making the last two rounds on the number. However, title holder Joonas Granberg of Finland missed the halfway cut by four shots despite a 70.
Scores after round 2 of the Worldwide Holdings Selangor Masters 2012 being played at the par 72, 6977 Yards Kota Permai GCC course (a- denotes amateur):
135 - Michael TRAN (VNM) 67-68, Thaworn WIRATCHANT (THA) 66-69.
136 - Marcus BOTH (AUS) 67-69.
137 - Javi COLOMO (ESP) 68-69.
138 - Kieran PRATT (AUS) 67-71, Lindsay RENOLDS (CAN) 68-70, Jonathan MOORE (USA) 67-71.
139 - Panuphol PITTAYARAT (THA) 67-72, Jesper KENNEGARD (SWE) 70-69, Gaganjeet BHULLAR (IND) 68-71, Scott HEND (AUS) 70-69, Vikrant CHOPRA (IND) 69-70, Gavin FLINT (AUS) 70-69.
140 - Mardan MAMAT (SIN) 68-72, Himmat RAI (IND) 70-70, Rattanon WANNASRICHAN (THA) 69-71, Jason KNUTZON (USA) 72-68, LAM Chih Bing (SIN) 70-70.
141 - Thammanoon SRIROJ (THA) 70-71, Panuwat MUENLEK (THA) 70-71, Ron HARVEY Jr (CAN) 71-70, Niall TURNER (IRL) 71-70, Rashid KHAN (IND) 69-72, Ajeetesh SANDHU (IND)