Despite being 35 years of age, the striker has enjoyed a solid start to life at his new V.League 1 club Nam Đinh.
Both matches were held behind closed doors to avoid the spread of the novel coronavirus.
The Việt Nam Professional Football Company (VPF) chose to ban supporters from all seven matches of the first round on March 6, 7 and 8 to ensure safety amid the coronavirus outbreak.
On his Facebook page, Mạnh said: "Is my leg hurt? Yes. Am I sad because of injury? Yes. Unfortunate for me, however, I will accept it and I will overcome difficulties and hardships."
Hà Nội FC lifted their third National Super Cup trophy after coming from behind to beat HCM City 2-1 yesterday at the Thống Nhất Stadium.
The organisers of the match have decided to hold the match in the empty venue because of the ongoing deadly coronavirus outbreak.
The second-round match in Kuala Lumpur is scheduled for March 31, but the South Korean coach's charges may not get much game time ahead of the match.
The deadly virus which has killed more than 300 people in China has spread to Việt Nam and forced the domestic football season's start to be delayed.
Hà Nội FC need to be at their very best to progress in the AFC Champions League, according to coach Chu Đình Nghiêm.