Lazio were crowned Italian champions for the second time in the club's history yesterday after they beat Reggina 3-0 in Rome and overnight leaders Juventus suffered a shock 1-0 defeat at Perugia.
Lazio, who won their only other league title back in 1974, but had been runners-up to AC Milan in 1999, finished the season with 72 points.
Juventus stayed on 71 points - their two point-lead over Lazio evaporating with their upset at Perugia in a match which was interrupted for 75 minutes due to a rainstorm.
They had been nine points clear at the top in late March but a run of defeats saw them caught by Lazio, who could yet do the league and cup double. The Rome club beat Inter Milan 2-1 in the first leg of the Italian Cup last month.
Lazio coach Sven Goran Eriksson said: "It wasn't just me, it was the team who did a great job. They believed they could do it right to the very end and now we've won. And we're just delighted.
"Winning the Serie is like winning the Champions League," the Swede added. Lazio were knocked out of the quarter-finals of Europe's premier club competition by eventual finalists Valencia.
Juventus were sporting in defeat with the club's honorary president Umberto Agnelli, saying: "Compliments to Lazio - a great team has won. We'll meet again next year. But thanks to Juventus for all they've done."
Alessandro Calori was the man who cost Juventus what would have been their 26th league trophy - firing home a volley just four minutes after play restarted.
Juventus finished the match with 10 men after winger Gianluca
Zambrotta was sent off for a second bookable offence - a nasty tackle on Massimiliano Esposito - with 20 minutes still to play.
As huge puddles of water formed across the pitch, players and match officials could only stand inside the plastic tents leading to the dugouts and watch the downpour.
After the delay, play eventually restarted with the goal which stunned the most successful club in the history of Italian soccer.
Calori collected a ball headed out by Juventus skipper Antonio Conte, controlled it with one touch and then unleashed a volley into the left-hand corner which beat van Der Sar.
Juventus threw everything they had against a team whose defeat to AC Milan in the final match of last season had denied Lazio the title and handed it to Milan.
Plumes of water sprayed up every time a player hit the ball or slid in for a tackle.
Their Ukrainian striker Andriy Shevchenko, who bagged Milan's second goal from the penalty spot, finished as the Serie A's top scorer in his debut season with 24 goals - a remarkable feat.
Bayer Leverkusen need a point in their final game next Saturday to win the German title, but could still be crowned champions if they lose. Bayern Munich trail by three points and have an inferior goal difference.
