The two fans were taken to the Infante Police Station in Porto, while an injured police officer was taken to Hospital Santo António to be sutured in the face.
With the Ribeira zone closed by PSP after the end of the game that Chelsea won 1-0, Manchester City fans headed for Avenida dos Aliados, from where the opponent fans also started, eventually ending up with some conflicts.
The PSP has had 1,000 agents on the ground to ensure that the festivities do not result in further incidents.
In a 100 percent English final, Chelsea won the Champions League and defeat Manchester City 1-0 in the final, in a game played at Estádio do Dragão, in Porto.