ARSENAL-NAPOLI Arsenal heads into the Europa League's last eight potentially needing to win the competition to secure a return to the Champions League next season. Finishing in the top four of the Premier League would also guarantee that and Arsenal is currently in fifth place, locked in a tight battle with Chelsea, Tottenham and Manchester United to claim the two qualifying spots behind Liverpool and Manchester City.
Five points separate Chelsea in third place and United in sixth, with Chelsea having played a game more than its three rivals. Ozil's five-match run in the team started in the 3-1 Europa League loss to Rennes in the first leg of the last 16. But Arsenal's 3-0 victory in the second leg kept alive Emery's bid to win the competition for the fourth time, after doing so with Sevilla in three straight years from 2014.
Napoli, which is second in the Italian league, won the now-defunct UEFA Cup — the precursor to the Europa League — in 1989. It is the club's only major European honor. A look at the other three quarterfinals:
SLAVIA PRAGUE-CHELSEA Chelsea, the 2013 champion, is in a similar position to Arsenal in needing to take the Europa League seriously to potentially earn a Champions League qualification place. Winning the competition would also provide its manager, Maurizio Sarri, with a first title in his 29-year coaching career.
Slavia Prague is widely regarded as the weakest team left in the Europa League, even though the Czech club surprisingly ousted Sevilla in the last 16. VILLARREAL-VALENCIA The clubs from eastern Spain are on opposite ends of the league standings, with Villarreal fighting against relegation and Valencia contending for a Champions League spot and preparing for the Copa del Rey final against Barcelona.
"We have done a good job separating both competitions," Villarreal coach Javi Calleja said. "There is no pressure for us in this competition, unlike in the Spanish league." Valencia got past Villarreal in the semifinals of the 2004 UEFA Cup, a competition it eventually won.
BENFICA-FRANKFURT Eintracht Frankfurt's season could hardly be going better under coach Adi Huetter, who replaced Niko Kovac in offseason. The club can match Atletico Madrid's record for 15 games unbeaten in the Europa League if it avoids defeat in Lisbon.
Frankfurt also is enjoying its best ever Bundesliga season, with 52 points after 28 matches. Benfica has never lost at home in any stage of the Europa League, with 18 wins and three draws.