Portugal won Euro 2016 without winning a single group game.
1-1 Iceland, 0-0 Austria, 3-3 Hungary: third in the group, just enough to go through.
Then Croatia 1-0, Poland on penalties, Wales 2-0, and France, the hosts, 1-0 in the final.
Seven games. Only three wins. Not a single defeat.
You don't have to win every game. You just can't lose the last one.