Scotland reached their first major international tournament since 1998 after a dramatic penalty shootout win over Serbia in their European Championships qualifying playoff.
The Scots looked to have blown their chance when conceding a late, late equaliser in Belgrade as Real Madrid striker Luka Jovic forced extra-time.
However, with the hosts in the ascendancy they held firm before triumphing 5-4 on penalties, Fulham striker Aleksandar Mitrovic seeing his spot-kick saved.
Scotland converted all their penalties and mobbed each other after their goalkeeper David Marshall saved the home side's final spot kick, diving to his left to keep out Mitrovic's shot.
Ryan Christie fired a dominant Scotland into a 52nd-minute lead with a superb shot on the turn before substitute Jovic equalised in the 90th when he headed home a Filip Mladenovic corner to force extra time.
Scotland will join the 24-nation tournament's Group D including England, the Czech Republic and 2018 World Cup runners-up Croatia, with matches in that pool to be played at Wembley and Hampden Park.
"It was never going to be easy,” Marshall told Sky Sports. “The first hour of the game we were completely dominant but the second goal just wasn't coming.
"I'm lost for words about how well the lads did to cope with that pressure when they got the equaliser.
"The manager, the players, Robbo all speaking (before the shootout) just changed the mentality. The last three or four games have given us that winning belief.
"I don't know how we did it. We deserved it after the first half especially. I'm just so happy."
Additional reporting by Reuters.
