Kyrgyzstan have been forced to play a World Cup qualifying match with a defender in goal because all three of the national team's keepers were self-isolating after a COVID-19 outbreak.
Defender Aizar Akmatov instead played between the posts in the 1-0 home loss to Mongolia in Group F.
Oyunbaataryn Mijiddorj scored in the 34th minute for the visitors.
Mongolia are ranked 192nd of FIFA's 211 teams. Kyrgyzstan are ranked 99th.
Also in Group F, Japan beat Tajikistan 4-1 for their seventh victory in as many matches in the second round of Asian qualifying.
Japan had already secured a place in the third round of qualifying.
Kyogo Furuhashi, Takumi Minamino, Kento Hashimoto and Hayao Kawabe all scored for Japan, while Ehsoni Panshanbe scored for Tajikistan - the first goal Japan has conceded in 549 minutes of play.
Syria became the second team to advance to the next phase of qualifying with a 3-0 win over Guam in Sharjah, for their seventh successive win in Group A.
Only the eight group winners progress automatically to the third round, which is set to start in September, along with the four best second-place teams.
China are eight points behind Syria but can only hope to finish second despite a 2-0 win against the Philippines.
The goals came from Wu Lei and Wu Xinghan but with just two games remaining.
Second-half goals from FC Zenit striker Sardar Azmoun and Mehdi Taremi of Porto gave Iran a 3-0 win over Bahrain and second place in Group C, two points behind Iraq who defeated Cambodia 4-1.
Uzbekistan thrashed Singapore 5-0 to move two points behind the inactive Saudi Arabia in Group D.
Vietnam remain top of Group G with a 4-0 win over Indonesia in Dubai.
United Arab Emirates moved into second, two points behind the leaders, defeating Thailand 3-1.