According to Gazzetta dello Sport, some Lazio supporters, who were traveling on the same flight with the team, verbally abused the Portugal midfielder.
Nani didn't take the attack lightly and things quickly turned physical, requiring the intervention of seven other people to prevent further harm.
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Upon arriving in Rome, one of the instigators was held in the plane until all the players disembarked.
Nani is with the club on a loan from Valencia and has scored three goals in 19 appearances during his spell.