There was disbelief among the majority of the crowd at the Wunna Theikdi Stadium as a lone, unfamiliar runner decked in a red top emerged first from the tunnel.
With barely a kilometre left in the 42.195km race, local favourite Aye Thuang had looked set to bag the gold in front of his countrymen.
But, as the lone runner strode into the Myanmar sunlight around 9am yesterday, it became clear the winner was going to be from another country.
And, as he made his way to the finish line, the cheers went up: "Mok, Mok, Mok."
Mok Ying Ren then held up his arms, breasted the tape and entered the history books as the first Singapore man to win a SEA Games marathon title.
The Singaporean clocked 2hr 28min 35sec to finish more than a minute ahead of Thuang (2:29.49), who slumped on the track after the race, beaten on the hilly route under a chilly 17 deg C weather.
Filipino Eric Panique, silver medallist at the 2011 SEA Games, was third in 2:30.29.
The Singapore flag draped over him, Mok, 25, had only two words to sum up his win: "Swee (Hokkien for beautiful), lah."
Beautiful it was, as he timed his run to near perfection, picking off his competitors one after another on the five-loop course.
He said: "There were a lot of mild hills on the course so I knew that I should not go out hard in the first two rounds.
"Then, every loop got tougher and tougher and people started dropping off the pace."
Cambodian Kuniaki Takizaki was the first among the eight runners to make his move, pushing the pace as early as the first loop.
Indonesia's Nikolas Sila then assumed the lead in the second round.
But, as predicted, the hilly terrain soon took its toll on the field.
By the final round, almost half the field had fallen off the pace. And though Mok trailed Thuang, Sila and Panique, he knew he had it in him to make his move.
Starting his attack around the 35km mark, the Singaporean upped his pace, passing one runner after another before taking the lead.
Said Mok, who overtook Thuang as they entered the gate of the 30,000-seater stadium: "When I passed him, and he didn't attempt to follow, I knew that I had the gold medal."
For Mok, who missed M. Rameshon's national record of 2:24.22 set in 1995, the race was not about timing but placing.
Said the 2007 Games triathlon champion: "This is not a race with a lot of runners where you set splits and try to achieve it. This is a race for gold with only eight competitors. Here, tactics and race strategies are more important so I wasn't going for timing but for position."
Mok's victory was all the more impressive as his training time was reduced as he is undergoing training as a medical officer as part of his national service.
The Singaporean, who is aiming for a place at the 2016 Rio Olympics, had arrived in Naypyidaw only on Sunday evening.
Not everyone, however, found the rolling hills of the race course as smooth as Mok.
Indonesia's defending champion Yahuza Yahuza, who managed a podium finish at the three previous editions, ended seventh in 2:36.32.
Singapore's other representative, Ashley Liew, was eighth, clocking 2:42.54.
He said: "This is the toughest race I have done.
"The 900m hill at the start will separate the leaders and you have to do it five times so it really affects your legs. "It's all about who has got the mental tenacity to win it.
"It's really a fighter's course."
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