Italy have failed to qualify for the World Cup for the first time since 1958 after they were held to a goalless home draw by Sweden in the second leg of their playoff.
The Swedes prevailed 1-0 on aggregate after they won the first leg on Saturday (NZT).
Sweden survived wave after wave of Italian attacks at the San Siro. The closest the hosts came to scoring was a Ciro Immobile effort which was partially stopped by keeper Robin Olsen and cleared away by Victor Lindelof as it was about to trickle over the line.
A tearful Gianluigi Buffon later called time on his 175-cap international career in the moments after the game ended.
The 39-year-old Juventus goalkeeper, who made his Italy debut in October 1997, kept a clean sheet against Sweden at San Siro.
In tweets from the national team's official account, he said: "We are proud, we are strong, we are stubborn.
"We will pick ourselves up as we have always done.
"I am leaving a national team set-up that will know how to pick itself up again.
"Best wishes to everybody, and especially to those with whom I have shared this beautiful journey."
Italy have won the World Cup four times, most recently in 2006 with Buffon one of the team's key personnel as they went on to defeat France in the final in a penalty shootout.
Buffon had already decided to hang up his Azzurri gloves after Russia 2018 and, with that opportunity stripped from him seven months before the tournament, he is taking his leave early.
"The blame is divided equally among all of us," he said.
"There must be no scapegoats.
"We win together and we lose together.
"I'm not feeling sorry for myself but I'm sorry about the whole affair.
"We blew something that could have meant so much.
"The main regret is that it ended like this."