If a noun denotes a group of people – even if it's technically a singular noun – it's okay (but not compulsory) to use a plural verb.

The sentences 'Real Madrid have performed well this year' and 'Real Madrid has performed well this year' are both grammatically acceptable, and probably used roughly the same amount.

A related example is the word 'none' (= 'not one'). Technically it should govern a singular verb (e.g. 'None of the players is good enough') but you'll now see it a lot with a plural verb (e.g. 'None of the players are good enough').