Porto overcame Colombia's Once Caldas to win the World Club Cup.
Defender Pedro Emanuel converted the decisive penalty in a shoot-out following a 0-0 draw after extra time.
Porto dominated the last annual match between the Champions League winners and the South American champions, with Benni McCarthy going closest.
Caldas survived to force a shoot-out which saw Porto's Diego sent off for taunting the goalkeeper before John Garcia crucially missed his penalty.
Porto lifted the trophy for the second time following their extra-time win over Penarol of Uruguay in 1987.
The tournament, which is held in Japan, is to change format next year when a club from each of football's six confederations will take part.