The champions, Juventus, slumped to a surprise 3-0 defeat at in-form Bologna while the league leaders, Fiorentina, endured a 0-0 stalemate at Bari - their first draw of the season.
At the Tardini stadium Enrico Chiesa made amends for an early miss to put Parma ahead in the 25th minute, turning home the loose ball after Sebastiano Rossi had failed to hold Dino Baggio's fierce shot from outside the area.
Within 11 minutes, Milan were 2-0 down as Crespo touched the ball over the advancing Rossi, and Crespo struck again 14 minutes after the break, a downward header punishing some slack defending. Alain Boghossian, the French World Cup midfielder, completed Milan's humiliation in stoppage time with his first goal since joining Parma from Sampdoria in the summer.
Juventus struggled from the start at Bologna's Dall'Ara stadium. Michele Paramatti was left unmarked in the third minute to head home Giuseppe Signori's free-kick. Five minutes later, the Croat Igor Tudor failed to clear Kennet Andersson's header and the rejuvenated Signori pounced to claim his fifth goal of the season.
Juve's nightmare start was completed in the 28th minute by Davide Fontolan, who first robbed Ciro Ferrara on the halfway line before exchanging passes with Andersson, dribbling round Mark Iuliano and beating the goalkeeper with a neatly placed shot.
After the break, Francesco Antonioli saved brilliantly from Filippo Inzaghi on two occasions as Bologna celebrated their first home success over Juve in 24 years. They are also unbeaten in 16 league and cup matches, while Juventus who are without a win in any competition since losing their top striker Alessandro Del Piero with ligament damage.
Internazionale scored twice in the last 15 minutes to defeat Salernitana 2-1. David di Michele had given the lowly visitors a deserved half-time lead before the Argentinian pair Diego Simeone and Javier Zanetti saved Inter with goals in the 76th and 90th minutes.
In Spain, Atletico Madrid spoiled the Barcelona party on Saturday as they battled their way to a 1-0 Spanish League victory on the night the Catalan club kicked off their centenary year celebrations.
A Vladimir Jugovic penalty six minutes before half-time proved enough to give Atletico their first away victory of the season and leave Barca fans voicing their dismay on an emotional night for the club, which was founded in 1899.
Celta Vigo, Liverpool's Uefa Cup opponents, were held to a 2-2 draw at home to Valencia. The Galicians had looked set for victory as they recoverd from Romania's Gabriel Popescu's 23rd minute opener with goals either side of half-time from Alexander Mostovoi and Juan Sanchez. But a superb strike from another Romanian international, Adrian Ilie, who blasted in from the edge of the area, secured a point for the visitors.
A header by Savo Milosevic, the former Aston Villa forward, after six minutes proved enough to give Real Zaragoza a 1-0 win at home to Oviedo.
In Germany, a Tony Yeboah hat-trick put an end to Hamburg's indifferent run of six games without a win. The former Leeds United striker was the star of Hamburg's 3-0 victory over struggling Borussia Monchengladbach. The Bundesliga leaders, Bayern Munich, cruised to a 2-0 home win over Nuremberg with goals by Giovane Elber and Bixente Lizarazu.Reuse content