Lâm suffered sprained ankle ligaments and could not recover before going to the training camp on Tuesday.
Coach Park Hang Seo has called up 48 players for a training camp to prepare for next year's Southeast Asian Games, where the U22 team will attempt to defend their crown.
Sơn, now a key part of the HCM City FC team, is keen to show his old club what they're missing.
A win, and only a win. That’s what Hà Nội FC’s young president Đỗ Quang Vinh wants from his team as the V.League 1 gets back in action on Friday.
The round will even feature a match between two teams from the first division as Cần Thơ and Bình Phước, meaning at least one V.League side will enter the quarter-finals.