Second-half goals from the Marcelo Salas, Dejan Stankovic and Roberto Mancini, after Renato Buso had cancelled out Sinisa Mihajlovic's first- half opener, gave Lazio a commanding win.
Parma were held to a disappointing scoreless draw at Vicenza while a resurgent Milan won 3-2 in dramatic style at Bologna.
The French defender Bruno N'Gotty scored with a 90th-minute free-kick, less than a minute after coming on as a substitute, to give Milan their first away victory since October and stretch their unbeaten league run to seven matches.
Roberto Baggio scored twice and laid on three other goals as Internazionale recovered from Roberto Muzzi's third-minute opener to thrash 10-man Cagliari 5-1 at San Siro, while Roma crashed 2-1 at lowly Salernitana.
Juventus's latest signing, Thierry Henry, made his Serie A debut against Perugia at the Delle Alpi, but his French compatriot Zinedine Zidane stole the limelight with a second-half winner in a 2-1 victory for the champions.
Nine-man Atletico Madrid survived a frantic final five minutes of their Spanish Primera Division game against Celta Vigo to win 2-1.
Victory for Arrigo Sacchi's side, who had Stefano Torrisi and Juan Antonio Chamot sent off in the second half, enabled Barcelona to take over from Celta at the top of the table with their fifth successive league victory, a 3-1 success at home to Real Zaragoza. Rivaldo scored twice in the second half.
Mallorca suffered their second successive defeat, going down 1-0 to a Claudio Lopez goal for Valencia, who are third.