When in Barcelona if you don't want to splash the cash on increasingly expensive stadium tickets, then the likelihood is you'll be heading to a bar to catch the big game. When Barça play the streets are emptied and most bars get cramped for standing space, let alone seats, so get their an hour early to reserve a perfect view of the TV.
Remember, we're talking about soccer here. If you're intereted in American football, check out this page on Barcelona Sports Bars
In El Born there are a number of good bars to catch a game, most of which have a very international feel and usually show Premiership games, as well as La Liga. This is the case with Bar Salvador on Carrer Canvis Nous, close to Via Leyetana and Santa Maria del Mar Church, which has imported beers and also shows big rugby games. If you don't mind a predominantly English-speaking crowd, there are two huge traditional Irish bars in the centre serving up sports events. These are Dunne's, on Via Layetana, and George Payne, in Plaça Urquinoana. Further out of the centre, Michael Collins is a favourite for Catalans as well as ex-pats, and is located within the shadow of La Sagrada Familia. Republic House, on Passeig de Sant Joan, also has a mixed local-ex-pat crowd, and will show pretty much any game you request.
For a more native football crowd, head to one of the bars along Avenida Diagonal close to the Camp Nou Stadium - part of the noise you'll hear will come from the stadium itself. Or try any of the grease-splattered old men's bars you'll find on almost every block in the city. They're cheap, noisy, friendly, and very partisan.
If you want to go to local game and enjoy some free live football right in the city centre, head to FC Barceloneta's stadium - which also has a very good bar with a huge screen - on Ronda Litoral. Here there are games all weekend, including those of an international league called the BIFL, which has teams from all over the world. This league has games at different stadiums around the city on saturdays, and a very lively social calendar. Also on Ronda Litoral, opposite Barceloneta metro station, is Pasatapas, a tapas and football institution, whose owner is an avid Espanyol fan.