Lionel Messi scored his 100th European goal as Barcelona maintained their winning run in Champions League Group D with a 3-1 home victory over Olympiacos.
A Dimitris Nikolaou own goal set the five-time European champions on their way but Gerard Pique's red card just before half-time gave the visitors a glimmer of hope.
Not for long, though, as Messi made it to his milestone with a lovely free-kick before setting up Lucas Digne as Barcelona made light of having just 10 men with quick-fire goals in the second half.
It will have been a great moment for teenager Nikolaou when he slightly redeemed himself by heading home Kostas Fortounis' corner for a consolation goal in injury time.
As the players emerged from the tunnel at the Nou Camp and out into the teeming rain, a huge banner was unfurled, calling attention to the current political situation in Catalonia.
Olympiacos will have been happy with their start, restricting the hosts to just an early half chance which Luis Suarez could not quite reach well enough to make a telling contact.
However, the Greeks fell behind after 18 minutes when Nikolaou stuck out a leg to divert Gerard Deulofeu's cross into his own net.
That affected the confidence of an Olympiacos team who have won only one of their last five matches domestically, and Paulinho had an effort ruled out for offside shortly afterwards before seeing a header hit the crossbar midway through the first half.
Vadis Odjidja-Ofoe had the visitors' first effort of the match after 36 minutes with a dipping volley that dropped just wide.
Olympiacos were then presented with a possibly route back into the match two minutes before half time when Pique was sent off. The Barcelona defender was booked early on for a cynical pull back on Odjidja-Ofoe and he received a second yellow card when Scottish referee Willie Collum decided he tried to deliberately score with his hand from a Deulofeu cross.
Deulofeu was replaced by Javier Mascherano at the break as Barcelona boss Ernesto Valverde sought an alternative at the back for Pique, while Olympiacos manager Takis Lemonis made an attacking switch as he brought on striker Uros Djurdjevic for midfielder Guillaume Gillet.
It was to no avail, however, as Messi doubled the lead for the 10 men after 61 minutes with a lovely free-kick.
The Argentina international was brought down by Nikolaou just outside the penalty area and regained his feet to curl the ball over the defensive wall and beyond the goalkeeper.
Three minutes later, Messi set up Digne to score with a low finish and put the game beyond doubt.
Messi was clearly enjoying himself and teed up Paulinho before Olympiacos goalkeeper Silvio Proto completed a brilliant double save by repelling Messi's follow-up.
Despite their numerical advantage the visitors struggled to create anything of note until Nikolaou went part way to atoning for his own goal by heading a consolation goal at the beginning of injury time for the group's bottom club.