There were scenes of wild celebration after the final whistle at Hampden and Robertson revealed the huge pressure he and his team-mates felt to end the 28-year wait to make it back onto the world’s biggest stage.
Robertson said: "I'm so glad it's ended up this way. This group of boys, this group of staff - it's the best group I've been involved in. The manager's (Steve Clarke) speech before the game was unbelievable. He went through the big moments we've had. Qualifying for the Euros - he couldn't quite remember - we were in Wunderbar. He said 'let's make it another one'. We were quite emotional. To do it for him, the staff and all our families, it'll go down as one of the greatest nights of my life. That just sums up this squad. Never say die. We just keep going right to the end and one of the craziest games. We put the country through it, but I'm sure it's worth it. We're going to the World Cup."
Addressing Kelly Cates (daughter of Anfield legend Kenny Dalglish), Robertson added: "I can't wait to get back down to Liverpool to have a red wine with yer da."
Midfielder John McGinn added: "I thought we were pretty rubbish to be honest, but who cares? To get over the line was such an amazing feeling. The gaffer's team talk was exceptional. It's a privilege every time we meet up. It's just humble guys wanting to do well for their country. We left everything out there. You think that's it - glorious failure, another blow. I was thinking about the play-offs in the 91st minute. But then what a hit from Kieran Tierney - I will never feel like that in a football stadium ever again."