Maybe they were struck by the 55,000 seemingly random red and white seats, designed based on a computer programme to make the new National Stadium look full even when not.
As Singapore forwards Iqbal Hussein, 21, and Sahil Suhaimi, 22, left the spanking new dressing rooms - that comes with a jacuzzi and two cold baths - and walked through the tunnel before stepping out on to the pitch for a historic first football training session, they immediately experienced goose bumps.
Speaking ahead of tomorrow's glamour friendly between the Singapore Selection and Italian champions Juventus, both youngsters offered the response: "Even without any fans, I'm so excited, I think I might pee in my pants."
They said it with a grin, of course, but the two players definitely were a little overawed, especially at the prospect of what lay ahead.
Football has taken them to many countries but these young guns have never played at such a cavernous stadium.
And from now until the end of their international careers, the new National Stadium will be their home.
After bulging the net in the temporary goals a few times from Iqbal's crosses, fast-rising star striker Sahil mused: "I just can't get enough of this feeling. I've never played at the old National Stadium, so this is a totally new experience for me. Just imagining a full house cheering us on is enough to get my adrenalin pumping.
"Of course, I want to be the first Singaporean to score here, I'll give everything I've got."
The 20-man Singapore Selection side - Khairul Amri has been ruled out through injury - comprise local stars and three foreign players from the Great Eastern-Yeo's S.League, Sirina Camara (Home United) and the Warriors duo of Miroslav Pejic and Nicolas Velez.
Led by national coach Bernd Stange, they will face Serie A giants Juventus, who are on a pre-season tour of the region.
Sahil's Courts Young Lions teammate Iqbal, the youngest member of Stange's squad, is more accustomed to the compact Jalan Besar Stadium.
"To play in the same team with new and experienced teammates like Hassan (Sunny), Baihakki (Khaizan) and Shahril (Ishak) in a new stadium, against a top team like Juventus, is a big honour," said Iqbal, whose only national cap came in a 1-0 friendly win over Cambodia last year.
"I've played friendlies in other countries, but nothing is as awesome as this. I'm looking forward to playing against world-class players like Paul Pogba and Andrea Pirlo and I know I have to step up if I get the chance to play."
Unlike Sahil and Iqbal, Young Lions alumni Hariss Harun has played at the old National Stadium, where he has rubbed shoulders with former Liverpool stars like Fernando Torres, Javier Mascherano and Xabi Alonso in a 5-0 defeat in 2009.
The 23-year-old has happier memories of the stadium, of course, none better than his international debut in 2007, when he became Singapore's youngest capped player at 16 years and 217 days.
Said Hariss: "I still remember the game - a 2-1 win over North Korea.
"It's been a long time since we've had a stadium of this size and stature, which can hold 55,000 fans. Hopefully, we can experience the fans coming out in full force again to support the Singapore team."
While Hariss is eager to experience an old feeling, he appreciates the brand-new facilities.
"We had benches and chairs scattered around a big space - that was what the dressing room was like at the old National Stadium," said the vice-captain of the national team.
"If we wanted to shower, we had to walk out of the changing room to another room, and sometimes you would share that room with the away team because the other shower room is further down the hallway.
"The new dressing room is much more professional - each player has his own personal space, and there's even a safe for us to keep our belongings.
"It's a great feeling out on the pitch, and what struck me was how close the stands are to the field.
"If there's a full house, we will definitely feel the support willing us on to score and win. It's up to the players and fans now to create an identity for the new National Stadium, to make it our fortress."
This article was first published on August 15, 2014.
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