Mahad Ahmed, 17, and Jasmine Main, 18, flew to Lausanne to hand over Glasgow's official submission to the International Olympic Committee in time for Monday's deadline.
The youngsters were waved off at Glasgow Airport by Olympic athlete and Commonwealth medallist Lee McConnell; leader of Glasgow City Council Gordon Matheson; Scottish International Development Minister, Humza Yousaf, and chairman of the British Olympic Association, Lord Moynihan.
And the Evening Times can reveal that one of Glasgow's major rivals in the race to host the Games – Poznan in Poland – has pulled out for financial reasons.
That leaves Buenos Aires in Argentina, Guadalajara in Mexico, Medellín in Colombia and Rotterdam in the Netherlands still in contention, with the winner to be named in July next year.
Lee McConnell said: "Glasgow is a special place to compete in as an athlete so it is exciting to think that the world's best young athletes could get their first taste of competing in the Olympics right here in front of such amazing crowds."
Humza Yousaf said the YOG would be an inspiring event: "This is a proud day for Scotland as we send off our young people to hand in what we hope will be a bid that will win us the privilege of hosting the YOG in 2018.
"Scotland has a growing and deserved reputation for staging successful world class events and winning the right to host the YOG would be a fantastic opportunity to showcase Scotland on the world stage."