A would-be astronaut who lost his bid to become the first Korean in space has vowed to do his best until the very end.

The would-be astronaut Ko San lost his bid after he violated training regulations, just a month before he was to travel to space. He was replaced last week by backup trainee Yi Soyeon.

Speaking to reporters outside Russia’s Yuri Gagarin Cosmonauts Training Center Monday, Ko said what happened was shameful, adding that he would work hard as a backup.

Center Chairman Vassily Tsibliyev said Yi and Ko were evaluated Monday on what they learned the past year with Russian astronauts, adding that they had the same training.

The cosmonauts training center will announce the results of the evaluation in a news conference on Wednesday. Yi and Ko will head to the Baikonur Cosmodrome in Kazakhstan next week.