Sevilla stayed firmly on course for a second consecutive Europa League crown when an Aleix Vidal double and a Kevin Gameiro strike secured a thumping 3-0 win at home to Fiorentina in their semi-final first leg on Thursday.
Chasing a record fourth triumph in Europe's second-tier club competition, Sevilla took the lead in the 17th minute at a festive Sanchez Pizjuan stadium when Vidal thrashed a low shot into the corner from a Carlos Bacca layoff.
The Spanish midfielder made it 2-0 to the Andalusians seven minutes into the second half when Vitolo released him into space on the right of the penalty area and he finished clinically past Fiorentina goalkeeper Neto.
Substitute Gameiro put the tie virtually beyond the Italians 15 minutes from time when he scored with his first touch just under 30 seconds after replacing Bacca following good work down the left from fullback Benoit Tremoulinos.
It was Sevilla's ninth win in a row at home in continental competition and their seventh in seven matches at the Sanchez Pizjuan in the latest edition of the Europa League.
"Fiorentina deserved to be here but we again demonstrated our strength at our stadium and got another positive result," Vidal told Spanish television.
"We cannot relax in the return because if they get into the game early on we could suffer," added the 25-year-old, who had never scored in nine previous European appearances.
"If we said that the tie was evenly balanced we would be lying. But I repeat that we cannot let our guard down because they could get a result like we got today."
Fiorentina's Serie A rivals Napoli squandered the lead and drew 1-1 at home to Ukrainian side Dnipro Dnipropetrovsk in their semi-final, first leg, with the return legs to be played in a week's time.
Sevilla won back-to-back UEFA Cups in 2006 and 2007 and can eclipse Inter Milan, Juventus and Liverpool, who each won the competition three times.
Dnipro snatch draw at Napoli
Dnipro Dnipropetrovsk substitute Yevhen Seleznyov snatched a late equaliser to earn a 1-1 draw at Napoli who spurned several chances in the Europa League semi-final, first leg on Thursday.
David Lopez put Napoli ahead early in the second half on a frustrating night for home striker Gonzalo Higuain, who saw four second half efforts saved before Seleznyov struck.
Argentina international Higuain was thwarted by goalkeeper Denys Boyko as the Serie A side pressed for a second goal.
Seleznyov then took advantage of slack Napoli defending to snatch an equaliser with nine minutes left to put the Ukrainians in pole position for a place in the final in Warsaw.
Napoli, whose only European triumph was lifting the UEFA Cup in 1989, struggled to break down a stubborn Dnipro defence in the first half in Naples and, on the only occasion they got through, Lorenzo Insigne's shot struck the post.
The hosts appeared to have done the hard part when Spaniard Lopez headed them in front five minutes after halftime.
A second goal looked imminent as gaps began to appear in the Dnipro defence, but Dnipro keeper Boyko had other ideas.
Higuain twice got clear on the right but Boyko saved both efforts with his legs, and did the same when the Argentine got free on the left for another chance.
The Dnipro stopper then tipped a rising shot over the bar after Higuain worked an opening on the edge of the area.
Dnipro, playing their 17th match of a campaign which began in the third qualifying round on July 30, hit back against the run of play with nine minutes left.
Artem Fedetskiy sent in a low cross from the right, the Napoli defence failed to clear and Seleznyov turned it in at the back post to completely change the complexion of the tie.