The was very open from the opening whistle and Hulk had already curled a free-kick over from a promising position before Víctor Valdés dived to his left to tip behind an angled shot from João Moutinho.
The first true opportunity fell to Pedro Rodríguez in the tenth minute, but he skyed the effort on to the roof of the Porto net when free in the area after Iniesta’s pass had been deflected into his path via the heel of Jorge Fucile.
Hulk was the next to flash a shot across goal and then Helton then took no chances with a rising Xavi shot from outside the box.
Typically as the half wore on, so did Barcelona’s influence, the pressure telling when Guarín, boxed in in his own half, prodded a hopeful ball backwards that was gratefully collected by the unmarked Messi. Messi then jinked his way past Helton and rolled in the 39th-minute opener
Porto had little choice but to come out and attack after the break, yet save for a deflected João Moutinho effort and a fierce long-range shot from Guarín, rarely troubled a Barça defence that was missing both Carles Puyol and Gerard Piqué.
Instead, there was more space for Josep Guardiola’s side to expolit on the counter attack and David Villa should have wrapped up the game but his low shot lacked punch and Helton smothered at his near post.
The Portuguese champions were still in the contest until the 86th minute, when Rolando collected a second yellow card and Porto’s first red. Barça wasted little time capitalising, substitute Fàbregas finishing delightfully before Guarín was dismissed in the final minute for a sliding challenge on Javier Mascherano.
Fabregas moved to Barcelona to win trophies, and he has added two to his collection within two weeks of joining Barcelona!