SINGAPORE — Korean Jeongwoo Ham surged into a two-shot lead at the halfway mark of the Singapore Open on Friday, setting up a tense weekend showdown at Sentosa Golf Club.

The 31-year-old Japan Golf Tour regular, still chasing his breakthrough international victory, backed up an opening 7-under 64 with a composed 68 to reach 10-under-par after 36 holes.

But the lead is far from comfortable.

Charging hard is Thai star Jazz Janewattananond, the 2019 champion, who stayed firmly in the hunt with a fiery 66 highlighted by seven birdies. He sits just two shots back, ready to pounce.

Ham’s round was a mix of resilience and nerves. He scattered four birdies against a lone bogey, repeatedly escaping trouble with a red-hot putter. Even after missing seven greens, he kept his card together with just 26 putts — a quiet display of survival under mounting pressure.

He credited his good work on the greens.

“The putts. The putts were the best. During critical moments, I hit the putts well and made use of the chances. My irons weren’t as good. My accuracy on the green wasn’t great but I think I overcame the critical moments with the putts,” Ham said.

Behind him, Janewattananond’s momentum built through the day as he peppered the course with aggressive iron play, briefly threatening to erase Ham’s advantage.

The top two finishers secure slots to The Open set 16-19 July at Royal Birkdale Golf Club in Southport.

Ham admitted he hasn’t given it much thought.

“I honestly wasn’t really thinking too much about The Open. I was feeling envious about the Korean players who were going to play at The Open, but since today’s round has ended well, now I really want to go as well,” he said.

Chan, Quiban make cut

Meanwhile, Aidric Chan slipped to 4-under after bogeys on two of his last five holes led to a 72.

Chan, who teed off at the back nine, sandwiched a birdie on the 16th hole with bogeys on 15 and 17. Birdies on the second and fourth holes briefly lifted him to 6-under before he dropped shots on the fifth and eighth that stalled his momentum.

Justin Quiban, on the other hand, salvaged a 73 after a tough round marked by two birdies against four bogeys.

Carl Corpus faded with four bogeys in the last five holes to finish on 75, missing the cut by two strokes on 3-over.

He joined Angelo Que and Sean Ramos who also failed to advance.

The leading scores after 36 holes:

10-under — Jeongwoo Ham (KOR) 64-68

8-under — Jazz Janewattananond (THA) 68-66

7-under — Tomohiro Ishizaka (JAP) 67-68, Gaganjeet Bhullar (IND) 67-68

6-under — Jack Thompson (AUS) 68-68,

5-under — Caleb Surratt (US) 68-69, Cory Crawford (AUS) 70-67

4-under — Aidric Chan (PHI) 66-72, Kieran Vincent (ZIM) 66-72, Bjorn Hellgrend (SWE) 70-68, Luis Masaveu (SPA) 67-71, Ryosuke Kinoshita (JAP) 67-71, John Catlin (US) 67-71, M.J. Maguire (US) 69-69, Kevin Yuan (AUS) 67-71, Charles Porter (US) 66-72

SELECTED:

3-over — Carl Jano Corpus 70-75

7-over — Angelo Que 73-78

12-over — Sean Ramos 80-74.