FC Porto reached the all-Portuguese Europa League final after it lost 3-2 at Villarreal on Thursday but advanced on a 7-4 aggregate score.
Cani stabbed home Marco Ruben's cross in the 17th minute to give Villarreal hope, but Porto striker Hulk silenced the crowd at El Madrigal Stadium in the 40th when his blast took a friendly deflection off defender Mateo Musacchio's foot before landing in the net.
Porto's Radamel Falcao broke Juergen Klinsmann's 15-year-old record with his 16th goal of the tournament in the 48th.
Joan Capdevila leveled the score in the 76th and Giuseppe Rossi scored Villarreal's third from the penalty spot in the 80th.
''We found the space we needed to get goals,'' said Porto coach Andre Villas-Boas. ''They had to take risks and push forward.''
Porto will play Braga on May 18 in Dublin after it eliminated fellow Portuguese side Benfica.
First-year coach Villas-Boas was now one step away from leading Porto to its first European title since Jose Mourinho guided the Dragons to the Europa League crown in 2003 and the Champions League in 2004.
The Portuguese champions also boosted their bid of winning the triple crown as they face Guimaraes in the Portuguese Cup final four days after the Europa League final.
Villarreal began strong, knowing that it had to score quickly to have any chance, and owned almost 80 percent of the possession early on.
Except for a sole occasion by Cristian Rodriguez four minutes in, Porto was content to protect its comfortable margin and wait to counterattack.
Porto goalkeeper Helton stretched to block a shot by Cani on the edge of area seven minutes before Villarreal's pressure paid off in the Spanish midfielder's opener.
The rhythm of play slowed down, but Villarreal continued to create chances. Santi Cazorla played Rossi through in the 32nd, but the Italy striker fired into the side netting with only Helton to beat.
After equalizing, Hulk had a shot to double his haul on halftime, but the Brazilian could not better Villarreal goalie Diego Lopez.
''We know that we are responsible for the loss,'' said Villarreal coach Juan Carlos Garrido, whose team allowed five second-half goals in the first leg. ''We know that the errors we committed there decided the knockout series.''
Freddy Guarin finally took advantage of Villarreal's high defensive line when he found Falcao alone in the area in the 48th for the Colombia forward's fifth goal of the semifinals.
Villarreal midfielder Marcos Senna returned after two months on the sidelines in the 67th.
Capdevila controlled a cross before firing past Helton to end Porto's perfect run of seven wins in as many away games before Rossi cashed in a foul by Nicolas Otamendi on Ruben in the area for his 11th goal of the tournament.
Villarreal, which was fourth in the Spanish league, remained perfect in eight games at home in the continental competition.
