Japan began their bid for a first Asian Games men's football gold since 2010 with a 3-1 win over Qatar on Wednesday, as Syria and Afghanistan pulled out.
Japan were cruising 2-0 at half-time after goals by Teppei Yachida and Kotaro Uchino, before Qatar hit back in the 79th minute through substitute Abdulla Al Sulaiti.
But just as the Qataris threatened to grab a point in the group-round match, defender Taichi Yamasaki popped up to make the game safe for Japan in the closing minutes.
The Games in the eastern Chinese city of Hangzhou do not officially open until Saturday, but several sports are already under way.
On Tuesday, the first day of action, South Korea launched their quest for a third men's football gold in a row with a 9-0 demolition of Kuwait.
The men's football competition has been hit by withdrawals, however, with Afghanistan and Syria pulling out on Wednesday from Group C.
That means group opponents Hong Kong and Uzbekistan are into the last 16 without kicking a ball.
India were thrashed 5-1 by hosts China on Tuesday but coach Igor Stimac said he was just pleased to be able to field a team.
"I'm happy because I see that some teams pulled out at the last minute (because) they couldn't get enough players," said the former international defender for Croatia.
"It's a big problem for the whole tournament now."
The Asian Games are outside FIFA's international window so clubs are not compelled to release players.
Asian Games football teams are made up of under-23 squads but they can have three overage players.
Football, beach volleyball, cricket, modern pentathlon, rowing, sailing and volleyball will all take place at the Games on Thursday.
