If all you knew about this Saturday’s match at FedEx Field was that FC Barcelona and Manchester United have faced off in two of the last three UEFA Champions League finals, you’d think that there’d be plenty of bad blood. Not so.

Let’s get one thing clear: This isn’t the Hatfields and McCoys. After each final — Barcelona won both — United fans made the rounds in the pubs where I was watching and congratulated those of us who were celebrating. They’re one of Europe’s classiest clubs, and I’m not just saying that because I married into a family of United fans.

Even if you can’t go wrong, you may as well go a little more right by backing FC Barcelona. Why? To start, those two titles are hardly all that its won recently. Since 2004, Barca (“BAR-suh”) has won three Champions League titles, one European Super Cup, five Spanish league titles, one King’s Cup, four Spanish Super Cups and the FIFA World Club Cup.

It’s also worth mentioning that if you want a team that won’t embarrass you off the field, Barca’s your club. While certain star British players spent the last few years cheating on their wives in increasingly inventive ways (one even sued Twitter to hide the affair), Barcelona is relatively scandal-free. Think of it this way: Wouldn’t you feel a little sheepish donning an Albert Haynesworth jersey these days?

Speaking of jerseys, Barcelona’s jersey also showcases the club’s character. It’s fairly common for soccer teams to sell jersey space as advertising. But for the last several years, Barca has paid Unicef $2 million per year to display their logo. This year, Barcelona has also accepted a sponsor: an educational charity from Qatar. Would you rather support a team backed by major corporations or one that pals around with human rights organizations?

Dominant as its become, Barca has been a historic underdog. It’s the preeminent team in Catalonia, a region that has often been uneasy as part of Spain. Throughout the 20th century, military dictator Francisco Franco severely punished the region for remaining loyal to the republic during the Spanish Civil War. During the war, his troops caught and executed Barca’s president. Afterward, Franco violently suppressed the Catalan language and culture through brutal crackdowns and “disappearances.” FC Barcelona was one of the remaining forms of organized cultural expression.

It’s indicative of the ties between team and region that — though most of its rivals (Manchester United included) are owned by global plutocrats — Barca’s club leadership is still democratically elected by season ticket holders.

Win or lose, Barcelona fans have a lot to be proud of. So if you’re looking for a community of local fans for when the regular season kicks off, FC Barcelona has a well-organized local fan club. We watch every game at the Elephant and Castle at 19th and I streets NW, so come join us. With any luck, you’ll get the chance to graciously accept kudos from United fans after next year’s Champions League final.

The writer, a PhD candidate at Georgetown University, was the 2010 winner of The Post’s America’s Next Great Pundit Contest.