Sevilla v Zenit: reporters' view

Strengths
Nick Aitken: Holders Sevilla FC have come to define the word 'effective': clinical in front of goal; resilient defensively; a constant threat from set pieces; and comfortable with or without the ball. After his side's round of 16 exit to the Andalusians, Villarreal CF coach Marcelino noted: "Sevilla have the ability to win games without necessarily playing that well." Within Unai Emery's favoured 4-2-3-1 formation, they have the strength in depth to maintain their shape and tempo.

Richard van Poortvliet: FC Zenit's players know each other's games inside out, with the introductions of Ezquiel Garay and Javi García adding extra defensive quality to a team that has few problems scoring in this competition. This increased defensive steel has proved to be the Russian Premier-Liga leaders' chief asset; even when they are not playing well, they tend not to concede.

Weaknesses
Nick Aitken: There are not many. The 21-year-old Sergio Rico has deputised superbly for goalkeeper Beto, Sevilla's 2013/14 final shoot-out hero having suffered the recurrence of a shoulder injury. Against a skilful Villarreal side, Emery's physical lineup were often forced to cede the initiative, yet with the likes of Carlos Bacca, Kevin Gameiro and Vitolo lethal on the counterattack, that hardly qualifies as a weakness.

Richard van Poortvliet: Zenit picked up seven yellow cards in their round of 16 decider at Torino FC, and as a result will travel to Spain for Thursday's first leg with four key players suspended: Hulk, Danny, Igor Smolnikov and Domenico Criscito. The loss of their two creative outlets, as well as both full-backs, could be a massive blow for a squad arguably lacking depth.

Form
Nick Aitken: Following four defeats in six Liga matches spanning late January and February, Sevilla went unbeaten in six in March – winning five and keeping five clean sheets. In the UEFA Europa League, they snuck through Group G in second place only to find their feet in the knockout phase, where they have beaten both VfL Borussia Mönchengladbach and Villarreal home and away.

Richard van Poortvliet: Ten points clear at the top of the Russian table and on course for a fourth title in eight seasons, Zenit's form in the UEFA Europa League has been decent too. They overcame a young, supremely talented PSV Eindhoven 4-0 on aggregate, and while André Villas-Boas's men were well below par in the last-16 second-leg loss in Turin, Zenit will be hoping that was just a blip.

European pedigree
Nick Aitken: The Blanquirrojos have won this competition every time they have reached the quarter-finals, in 2005/06, 2006/07 and 2013/14. What's more, they are unbeaten at home in UEFA competition since 13 March 2014 – a 2-0 reverse to city rivals Real Betis Balompié in their UEFA Europa League round of 16 first leg, with Emery's team replicating that scoreline in the return before prevailing on penalties.

Richard van Poortvliet: Zenit looked destined to take Europe by storm following their UEFA Cup triumph in Manchester in 2008, but despite recruiting assorted top-class players they have not come close to repeating that success. This is the first time they have gone beyond the round of 16 since lifting the trophy.

One to watch/game changer
Nick Aitken: Criticised in the past by Sevilla fans for his profligacy in front of goal, since the turn of the year Vicente Iborra has found the composure he previously lacked. Customarily deployed in central midfield or behind a lone frontrunner, Iborra's stamina, steel, aerial power and well-timed late runs are key ingredients in Emery's tactical scheme. "You have to keep working and getting into positions," the 27-year-old said. "If you do that the goals will come."

Axel Witsel©AFP/Getty Images

Richard van Poortvliet: With the mercurial Hulk banned for the first leg, Axel Witsel could be the main man. The 26-year-old Belgium midfielder has found the net only twice in the 2014/15 Premier-Liga and once in the UEFA Europa League, yet his goals are not as important as his presence. His passing and role as a defensive shield make him the heartbeat of the side.

Prediction
Nick Aitken: Victorious in all four knockout fixtures so far, Sevilla were certainly more vulnerable in their group encounters, with doughty defending, fine goalkeeping and admirable finishing required under heavy pressure. "This team is mentally strong and knows how to weather a storm," said Emery after the Villarreal tie. When Zenit visit the Estadio Ramón Sánchez Pizjuán, a clean sheet to take to Russia will be a priority.

Richard van Poortvliet: Severely depleted, Zenit have it all to do in the away game. For Villas-Boas, it is imperative that they have something to play for come 23 April, so Zenit may be more defensive than usual in Seville where a draw would be an excellent outcome.

Possible starting XI
Sevilla: Rico, Figueiras, Trémoulinas, Carriço, Pareja; Mbia, Iborra, Vidal; Banega, Vitolo; Bacca.

Zenit: Lodygin; Anykov, Garay, Lombaerts, Neto; Javi García, Witsel, Mogilevets; Shatov, Rondón, Ryazantsev.