Benfica swept aside Barcelona to heap more pressure on boss Ronald Koeman, whose side have made their worst start to a Champions League campaign and are in danger of not featuring in the knockout stage for the first time in 18 years.
Barca – also beaten 3-0 by Bayern Munich earlier this month – have lost their opening two matches in the competition for the first time, and sit bottom of Group E.
Benfica got off to an energetic start and opened the scoring inside three minutes, when Darwin Nunez cut inside and finished low into the near corner.
Rafa Silva then clipped in a second after the break and Nunez netted a penalty in a comfortable victory for the home side.
Nunez also hit the post from out wide after rounding stranded Barcelona goalkeeper Marc-Andre ter Stegen, who made a rash decision to charge out of his area.
Luuk de Jong missed a glorious chance to level for the visitors early in the first half when presented with a seemingly open goal.
But Barca only registered one effort on target and had Eric Garcia sent off for a second booking with three minutes remaining.
Defeat means Barcelona face the prospect of not making the knockout stage for the first time since the 2003-04 season, when they did not qualify for the Champions League.
The last time they failed to progress from the first group stage when playing in the competition was in the 2000-01 campaign.
- 4Veríssimo da Silva
- 30OtamendiBooked at 33mins
- 22LazaroSubstituted forJuniorat 45+1′minutes
- 28WeiglBooked at 72mins
- 20João Mário
- 3GrimaldoBooked at 62minsSubstituted forMagalhães de Almeidaat 75′minutes
- 27Ferreira SilvaBooked at 56minsSubstituted forAfonso Fernandesat 86′minutes
- 15YaremchukSubstituted forTaarabtat 75′minutes
- 9NúñezSubstituted forMatias Ramosat 86′minutes
- 7Sousa Soares
- 18Cunha Pereira de Pinho
- 21Afonso Fernandes
- 34Magalhães de Almeida
- 77Aleixo Leite
- 83Carvalho Fernandes
- 88Matias Ramos
- 91Rodrigues da Silva
- 1ter Stegen
- 3PiquéBooked at 12minsSubstituted forPaez Gaviriaat 33′minutes
- 24GarcíaBooked at 87mins
- 20RobertoSubstituted forMinguezaat 89′minutes
- 21de Jong
- 5BusquetsSubstituted forGonzález Iglesiasat 68′minutesBooked at 86mins
- 2DestBooked at 78mins
- 16González LópezSubstituted forCoutinhoat 68′minutes
- 17de JongSubstituted forFati Vieiraat 68′minutes
- 6Puig Martí
- 10Fati Vieira
- 13Murara Neto
- 26Peña Sotorres
- 28González Iglesias
- 30Paez Gaviria
- Daniele Orsato
Match ends, Benfica 3, Barcelona 0.
Second Half ends, Benfica 3, Barcelona 0.
Foul by Ansu Fati (Barcelona).
Nicolás Otamendi (Benfica) wins a free kick in the defensive half.
Offside, Barcelona. Philippe Coutinho tries a through ball, but Memphis Depay is caught offside.
Philippe Coutinho (Barcelona) wins a free kick in the defensive half.
Foul by Julian Weigl (Benfica).
Substitution, Barcelona. Óscar Mingueza replaces Sergi Roberto.
Second yellow card to Eric García (Barcelona) for a bad foul.
Foul by Eric García (Barcelona).
Gonçalo Ramos (Benfica) wins a free kick in the attacking half.
Substitution, Benfica. Gonçalo Ramos replaces Darwin Núñez.
Substitution, Benfica. Pizzi replaces Rafa.
Nico González (Barcelona) is shown the yellow card for a bad foul.
Foul by Nico González (Barcelona).
João Mário (Benfica) wins a free kick in the defensive half.
Ansu Fati (Barcelona) wins a free kick on the left wing.
Foul by Lucas Veríssimo (Benfica).
Goal! Benfica 3, Barcelona 0. Darwin Núñez (Benfica) converts the penalty with a right footed shot to the bottom right corner.
Sergiño Dest (Barcelona) is shown the yellow card for hand ball.