The 21-year-old has been given time off to recuperate from an ankle injury.
Singapore head coach Bernd Stange says he is wary of pushing the younger members of his squad too hard after resting defender Safuwan Baharudin.
Just half of German’s 23-man squad are taking part in the preparations for the Asian Cup Group A qualifier against Oman on August 14 with Safuwan one of the more notable absentees.
The 21-year-old Lions XII star was missing from training at the Jalan Besar Stadium over the weekend after being granted time to recover from a niggling ankle injury before joining up with his international team-mates on Monday.
After playing a starring role in his club side’s Malaysian Super League triumph last term, and playing virtually non-stop since making his S-League debut in July 2009, Safuwan is prone to burnout and Stange figures resting his young players will limit the damage it can cause later in their careers.
“A player like Safuwan must rest once in a while,” Stange told AsiaOne.
“He’s very young, so we’ll try to protect him and he cannot play all the time. He needs to learn that sitting on the bench sometimes is okay, too.
“If we look after him well enough, he is a player who can develop and play at a high international standard.”