Match ends, Barcelona 7, Celtic 0.
Lionel Messi scored his sixth Champions League hat-trick as rampant Barcelona inflicted on Celtic their heaviest ever European defeat.
The Argentina forward cracked in an early first goal in the Group C match.
Celtic's Moussa Dembele had a penalty saved before Messi poked in his second.
In the second half, Neymar's free-kick sailed into the net, Andres Iniesta volleyed a fourth, Messi slid home the fifth and Luis Suarez scored with a volley and then a side-footed finish.
266 goals & 128 assists
In their two full seasons together at the Nou Camp, Messi, Neymar and Suarez have scored a combined 253 goals and assisted 120 more.
Those numbers are rising quickly in the early weeks of this season - 266 goals and 128 assists - and in this latest masterclass, Messi got a hat-trick and Neymar a goal and four assists.
They are - more often than not - unplayable. All of the weaknesses in Celtic's make-up - and there were so many - were ruthlessly exposed.
Messi scored after just three minutes when Neymar slid the ball through a spooked defence.
Celtic won a penalty against the run of play when Dembele was brought down by Marc-Andre ter Stegen, but the striker had his effort saved by the Barcelona goalkeeper.
After that, the floodgates opened.
Football as art
Messi's second came after he and Neymar combined to bamboozle the Celtic defence, Messi walking it in for number two. Barca's speed of thought and movement was delicious. Football, yes, but not as anybody in Scotland knows it.
Neymar's 50th-minute free-kick made it three, Celtic goalkeeper Dorus de Vries getting a touch but not a big enough touch. De Vries should have done better.
The torture just got worse. Iniesta came on at the break and scored the fourth, thumping Neymar's cross on the volley past De Vries.
Celtic's brains were spinning. Within 76 seconds the fifth had arrived, Suarez putting it into the box for Messi to slide in for his hat-trick goal.
Suarez added the sixth, taking down Neymar's dinked pass on his chest before turning and rifling it home.
Wrong kind of history
This was Celtic's heaviest ever defeat in Europe even before Messi assisted once again for the seventh, which Suarez. scored.
Celtic are just another in a long line of Barca victims. The Catalans have done this kind of thing to so many teams in the recent past and that is the only consolation for the visitors.
Celtic manager Brendan Rodgers said on Monday that great players always find space no matter what their opponents try to do to stop them.
Barca had the freedom of the Nou Camp - and they revelled in it to make Celtic suffer.
- 1ter StegenBooked at 23mins
- 4RakiticBooked at 40minsSubstituted forIniestaat 45'minutes
- 5BusquetsSubstituted forRafinhaat 61'minutes
- 21André Gomes
- 24de Vries
- 2K Touré
- 28SviatchenkoSubstituted forO'Connellat 68'minutes
- 27RobertsSubstituted forArmstrongat 68'minutes
- 8BrownBooked at 56mins
- 6BittonSubstituted forMcGregorat 76'minutes
- Ovidiu Hategan
- Shots on Target
Second Half ends, Barcelona 7, Celtic 0.
Offside, Celtic. Scott Sinclair tries a through ball, but Moussa Dembele is caught offside.
Goal! Barcelona 7, Celtic 0. Luis Suárez (Barcelona) right footed shot from very close range to the bottom right corner. Assisted by Lionel Messi following a corner.
Corner, Barcelona. Conceded by Dorus de Vries.
Attempt saved. Lionel Messi (Barcelona) left footed shot from outside the box is saved in the bottom left corner. Assisted by Luis Suárez.
Offside, Barcelona. Jordi Alba tries a through ball, but Luis Suárez is caught offside.
Foul by Rafinha (Barcelona).
Scott Brown (Celtic) wins a free kick in the defensive half.
Substitution, Celtic. Callum McGregor replaces Nir Bitton.
Goal! Barcelona 6, Celtic 0. Luis Suárez (Barcelona) left footed shot from the left side of the six yard box to the top left corner. Assisted by Neymar with a through ball.
Foul by Rafinha (Barcelona).
Stuart Armstrong (Celtic) wins a free kick in the defensive half.
Corner, Barcelona. Conceded by Eoghan O'Connell.
Attempt blocked. Rafinha (Barcelona) left footed shot from the centre of the box is blocked. Assisted by Neymar.
Offside, Barcelona. Lionel Messi tries a through ball, but Luis Suárez is caught offside.
Substitution, Celtic. Eoghan O'Connell replaces Erik Sviatchenko.
Substitution, Celtic. Stuart Armstrong replaces Patrick Roberts.
Offside, Barcelona. Lionel Messi tries a through ball, but Gerard Piqué is caught offside.
Corner, Barcelona. Conceded by Erik Sviatchenko.