Parting gift: Barcelona's Andres Iniesta celebrates scoring the fourth goal
Two goals from Luis Suarez and one from Lionel Messi put Barca 3-0 ahead at half-time with Iniesta, tipped to move to China at end of the season, on target after a smart shimmy in the 54th minute.
Philippe Coutinho hit the fifth from the penalty spot as Barca cruised to a 30th Copa del Rey triumph.
The last team to win the Cup four seasons running was Athletic Bilbao in the early 1930s.
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