Two of Europe's form clubs will clash when the Europa League knockout stage begins in earnest on Thursday.
Villarreal, fourth in the Primera Division, host Napoli, who were top of Serie A prior to their 1-0 defeat against Juventus at the weekend that saw the Old Lady leapfrog them.
Villarreal have not lost in the league since November but defender Daniele Bonera feels they must make the most of home advantage in the first leg of the last-32 clash.
The Italian told Villarreal's website: "San Paolo is a very difficult stadium to play at. People live all week for the match at the weekend. We will have to have a good game in the first leg because it will be really tough when we go there.
''In Italy they really respect Villarreal and we also respect Napoli, but we're not scared of them. They know they're going to have a really tough match against us.''
Manchester United dropped into the Europa League after finishing third in their Champions League group and will take on Danish side FC Midtjylland.
They will have to do so without captain Wayne Rooney, who is expected to miss around six weeks with a knee injury.
Boss Louis van Gaal said: ''We have 13 players injured and Wayne is one of them.
''He (got) injured in the game versus Sunderland and has a knee problem. He scores a lot of goals so he is very important for us. We know that but we have to cope with that."
Jurgen Klopp makes his first return to Germany as Liverpool manager for their clash with Augsburg.
The match has been described as the biggest in Augsburg's history, and the presence of Klopp, who left Borussia Dortmund in the summer before taking over at Anfield, only accentuates that.
The man himself played down the significance, saying: " I was there for 47 years, it's no problem. I know this country, I will not be surprised.
''It is more special for other people because there are not too many German managers working in foreign countries."
Tottenham, the third English team in the knockout stages, take a break from their Premier League title bid to face Fiorentina.
Spurs are looking to win the domestic title for the first time since 1961, but boss Mauricio Pochettino insisted they are targeting Europa League success as well.
Pochettino, who will be without goalkeeper Hugo Lloris through injury in Florence, said: " For us it is important, too.
''I can understand, because of our position in the table, it is a very big opportunity to fight for the Premier League but, for me, when you're in a big club like Tottenham, you need to fight in every competition and every game."
Valencia boss Gary Neville will hope to mark his managerial debut in the Europa League with victory over Rapid Vienna on his 41st birthday after finally breaking his league duck at the weekend.
Spain has four representatives in the last 32, with Athletic Bilbao travelling to Marseille and champions Sevilla hosting Molde.
Along with Molde, Midtjylland and Augsburg, Krasnodar are making their first appearance in the knockout stages of the competition and will take on Sparta Prague.
Borussia Dortmund, second in the Bundesliga, face Porto, whose Portuguese rivals Sporting Lisbon play Bayer Leverkusen.
Lazio travel to Galatasaray, while in the other ties Anderlecht meet Olympiacos, St Etienne host Basel, SC Braga travel to Sion and Shakhtar Donetsk play Schalke.
Source: PA
