Barcelona face a ban from the Champions League, Germany’s Welt am Sonntag newspaper reported on Friday, citing unnamed sources. The Spanish champions are alleged to have breached financial rules of the European governing body UEFA. According to the report, Barça is said to have included invalid funds in its most recent three-year balance sheet. UEFA did not want to comment and the club also has not commented. Expenses must be offset by “revenue directly attributable to the football business.” Barça reported a net profit of €304 million ($335 million) in September. However, the report said this…