With coach Singapore V. Sundramoorthy expected to stick with a 3-4-3 formation, competition for spots is fierce ahead of Singapore's international matches away to Qatar and Turkmenistan.
The Lions face Qatar in Doha on Thursday before the crucial AFC Asian Cup qualifier against Turkmenistan on Oct. 10.
"Everyone wants to be in the first 11, so we're giving our all during training to impress," defender Emmeric Ong told ESPN FC. "It's a very healthy competition between the players.
Warriors' Ong, who earned his first international cap in September's 1-1 friendly draw with Hong Kong, is a member of a 24-man squad hoping to play some part in Thursday's hit out against the 2022 World Cup hosts.
"For myself, I'm really looking forward to the Qatar game as it's another opportunity for me to represent the nation," he said.
"It's a tough game against a quality opponent, but the ultimate objective is the Turkmenistan game. So the performance here is key, and getting a favourable result will put us in good stead for next Tuesday."
Singapore have a poor record against Qatar, having won just once in 12 encounters.
The Lions have lost their last five games without scoring any goals against the Middle East nation, most recently falling to a 4-0 loss in Aug. 2015.
The Singapore squad have settled down well in hot Doha, trying to get acclimatised to the conditions at Jassim Bin Hamad Stadium on Thursday night.
The Lions took off from Singapore's Changi Airport around 10.30 a.m. on Sunday and reached after a nine-hour flight. Sundramoorthy led the 24-man squad in a training session for four hours after arriving, before putting them through their paces again on Monday.
In Doha, the temperature rises to as high as 38 degrees C in the middle of the day, under the harsh, desert sun. Nonetheless, the Lions are in high spirits.
"We were a little tired from the flight, but we've recovered well after a good night's rest," Ong said.
"The weather's pretty hot, but we're adapting well since it's pretty much like this in Singapore as well. Everyone's mingling well with each other, and the team spirit has been great."
Singapore's last trip to West Asia saw them secure a creditable 0-0 draw away to Bahrain in their opening AFC Asian Cup qualifier on March 28.
Singapore squad vs. Qatar and Turkmenistan
Goalkeepers: Hassan Sunny (Home United), Izwan Mahbud (Tampines Rovers), Zaiful Nizam (Balestier Khalsa)
Defenders: Shannon Stephen, Daniel Bennett, Mustafic Fahrudin, Madhu Mohana (Tampines Rovers), Emmeric Ong, Ho Wai Loon (Warriors FC), Faritz Hameed (Geylang International), Rusyaidi Salime (Garena Young Lions), Irfan Fandi (Home United)
Midfielders: Hariss Harun, Izzdin Shafiq, Faris Ramli (Home United), Hafiz Sujad, Shahdan Sulaiman (Tampines), Zulfahmi Arifin (Hougang United), Safuwan Baharudin, Yasir Hanapi (PDRM FA), Shahril Ishak (Warriors)
Forwards: Khairul Amri, Fazrul Nawaz (Tampines), Ikhsan Fandi (Young Lions)