Barcelona have announced losses of €97 million (£88m/$114m) for the 2019-20 economic year and blamed the coronavirus pandemic for a €203m (£184m/$239m) decrease in revenue.
The Catalan club finished the year with revenue of €855m (£775m/$1bn), which they said could have been a record-breaking €1 billion (£950m/$1.25bn) were it not for the Covid-19 outbreak.
Barca decreased their expenses by €74m (£67m/$87m) but still suffered significant losses, although the extension of the season beyond June 30 meant profit and loss items from the end of the season were transferred to the 2020-21 financial year.
There would have been a profit rather than a loss of €97m had it not been for the pandemic, according to the club.
A club statement read: "FC Barcelona has not been immune to the outbreak of Covid-19, but its consequences have had a massive effect on the entire sports industry.
"There has been widespread loss of revenue among all clubs in all the major leagues due to the restrictions that had to be applied to curb the spread of the disease, including competitions first being suspended and then resuming but with matches being played behind closed doors.
"The ECA [the European Club Association] has estimated the overall loss at around €4bn (£3.6bn/$4.7bn) and Barca, as one of the largest clubs in Europe and with such extensive diversification of its income, is one of the most affected.
"The club suffered financially from the consequences of games being played behind closed doors, as well as the total cancellation of the basketball Euroleague, and hence there was a considerable loss of income.
"The lack of tourists and visitors to the city of Barcelona due to the reductions and limitations applied to international tourism also meant far fewer visitors to Barca's premises, meaning major losses in terms of such areas as visitors to the Camp Nou Experience and the sale of products in official stores."
Barca are provisionally estimating €791m (£717m/$932m) in revenue for the 2020-21 financial year.
The disappointing financial news is the latest PR blow for Barcelona, who have been dogged by infighting off the field as well as poor results on the pitch, having lost the Liga title last season to Real Madrid and been thrashed 8-2 by Bayern Munich in the Champions League quarter-finals.