Query: What year did Barcelona claim to be a professional football club?
Context: As a reprisal, the ground was closed for six months and Gamper was forced to relinquish the presidency of the club. This coincided with the transition to professional football, and, in 1926, the directors of Barcelona publicly claimed, for the first time, to operate a professional football club. On 3 July 1927, the club held a second testimonial match for Paulino Alcántara, against the Spanish national team.