Teams still alive in the UEFA Europa League could enter up to three new A-list players before midnight on Tuesday 2 February. Now that the deadline is up, UEFA.com brings you all the details.
Remember: no matter what competition each player has played in the group stage, all of them can participate in the knockout rounds. See article 43 of the official competition regulations for more details.
Ajax
High: Ousama Idrissi (Sevilla, on loan)
Low: Klaas-Jan Huntelaar (Schalke), Victor Jensen (Nordsjælland, cedido)
Antwerp
High: Felipe Avanetti (Standard de Lieja, ceded), Didier Lamkel Zé, Maxime Le Marchand (Fulham, ceded)
Low: Cristian Benavente (Charleroi, loan), Simen Juklerød, Benson Manuel (Zwolle, loan)
Arsenal
Look at Lacazette’s goal for Arsenal
High: Gabriel Martinelli, Martin Ødegaard (Real Madrid, loan), Mat Ryan (Brighton, loan)
Low: Sead Kolašinac (Schalke, cedido), Matt Macey (Hibernian), Ainsley Maitland-Niles (West Brom, cedido), Shkodran Mustafi (Schalke), Joe Willock (Newcastle, cedido), Rúnar Rúnarsson
Benfica
High: Branimir Kalaica, Lucas Veríssimo (Santos)
Low: Ferro (Valencia, loan), Jean-Clair Tobido (end of loan)
Braga
High: Cristián Borja (Sporting CP), Andraž Šporar (Sporting CP, loaned), Lucas Piazón (Chelsea)
Low: Paulinho (Sporting CP), Guilherme Schettine (UD Almería, ceded), Iuri Medeiros
Witches
High: Bas Dost (Eintracht Frankfurt), Nabil Dirar (Fenerbahçe, cedido), Stefano Denswil (Bolonia, cedido)
Low: Krépin Diatta (Monaco), Siebe Schrijvers (Leuven), Emmanuel Dennis (Köln), Simon Deli (Slavia Praha, cedido), Michael Krmenčík (PAOK, cedido), Siebe Schrijvers (OH Leuven)
Red Star
High: Filippo Falco (Lecce), Axel Bakayoko (International), Slavoljub Srnić (fin de contrato)
Low: Veljko Simic (Vojvodina), Srdjan Spiridonovic (Genclerbirligi, cedido), Richmond Boakye (fin de contrato)
Zagreb Dynamo
High: Marijan Cabraja (Gorica), Josip Misic, Stefan Ristovski (Sporting CP)
Low: Mario Ćuže (Lokomotiva, cedido), Roko Jurišić (Rijeka), Josip Šutalo (Istria, cedido)
Dynamo of Kiev
Great goals for Dynamo Kiev in the Europa League
High: Artem Besedin, Sidcley
Low: Heorhii Tsitaishvili (Vorskla, cedido), Clayton
Granada
High: none
Low: none
Hoffenheim
High: Georginio Rutter (Rennes), Chris Richards (Bavaria, cedido)
Low: João Klauss (Standard de Lieja, ceded), Jacob Bruun Larsen (Anderlecht, ceded)
Krasnodar
High: Denis Adamov, Alexei Ionov
Low: Maksim Kutovoi, Andrei Sinitsin (fin de contrato)
Leicester
High: Daniel Amartey
Low: Kiernan Dewsbury-Hall (Luton, cedido), Wes Morgan
Leverkusen
High: Demarai Gray (Leicester), Timothy Fosu-Mensah (Manchester United), Jeremie Frimpong (Celtic)
Low: Santiago Arias, Julian Baumgartlinger, Lennart Grill
LOSC
Golazos of the Leverkusen in the Europa League
High: none
Low: Fatigue Ouattara (Valencia, ceded), Cheikh Niasse (Panathnaikos), Adama Soumaoro (Bolonia)
Maccabi Tel-Aviv
High: André Geraldes (APOEL), Uroš Nikolić, Matan Josez
Low: Roslan Barsky (Hapoel Haifa, on loan), Ben Bitton, Ronen Hanzis (Beitar Tel-Aviv, on loan), Tal Torgeman
Manchester United
High: Nathan Bishop, Amad Diallo (Atalanta), Phil Jones
Low: Facundo Pellistri (Alaves, on loan), Timothy Fosu-Mensah (Leverkusen), Jesse Lingard (West Ham, on loan), Odion Ighalo (end of loan)
Milan
High: Mario Mandžukić (free agent), Soualiho Meïté (Torino, loan), Fikayo Tomori (Chelsea, loan)
Low: Léo Duarte (İstanbul Başakşehir, cedido), Andrea Conti (Parma, cedido), Lorenzo Colombo (Cremonese, cedido), Mateo Musacchio (Lazio), Jens Petter Hauge
Molde
High: Emil Breivik, David Datro Fofana (Angers, cedido), Björn Sigurdsson (Lillestrøm)
Low: Henry Wingo (Ferencváros), Leke James (al-Qadisiyah), Mattias Moström (end of contract)
Naples
Golazos of the Milan in the Europa League
High: none
Low: none
Olympiacos
High: Kenny Lala (Strasbourg), Oleg Reabciuk (Paços Ferreira), Sokratis Papastathopoulos (Arsenal)
Low: Pape Abou Cissé (St-Étienne, ceded), Hilal Soudani (Al-Fateh), Bruno (Aris), Pêpê (Famalicão, ceded), Rúben Vinagre (fin de cesión)
PSV
High: Erick Gutiérrez, Fredrik Oppegård, Dante Rigo
Low: Djenairo Daniels, Kristófer Kristinsson, Rico Zeegers (Maastricht, cedido), Jorrit Hendrix (Spartak de Moscú)
Rangers
High: Jack Simpson (Bournemouth), Scott Wright (Aberdeen)
Low: Brandon Barker (Oxford, cedido), Nicky Hogarth (Cowdenbeath, cedido), Dapo Mebude (Queen of the South, cedido), Cameron Palmer (Linfield), Jack Thomson (Clyde, cedido), Ben Williamson (Arbroath, cedido)
Real society
High: Carlos Fernández (Seville)
Low: Willian José (Wolves, on loan)
Roma
High: Daniel Fuzato, Stephan El Shaarawy (free agent)
Low: Federico Fazio, Juan Jesus
Salzburg
Golazos of Villarreal in the Europa League
High: Nico Mantl (Unterhaching), Bernardo (Brighton, loan), Brenden Aaronson (Philadelphia)
Low: Dominik Szoboszlai (Leipzig), Masaya Okugawa (Bielefeld, loan), Jérôme Onguéné (Genoa, loan), Majeed Ashimeru (Anderlecht, loan)
Shakhtar Donetsk
High: none
Low: Alexander Drambayev (Mariupol), Viktor Kovalenko (Atalanta), Vladyslav Vakula (Mariupol, cedido)
Slavia de Prague
High: Alexander Bah (SonderyskE), Simon Deli (Club Brugge, cedido), Jakub Hromada
Low: Petar Musa (Union Berlin, cedido), Ondřej Karafiát (Liberec, cedido), Tomáš Malinský (Mladá Boleslav, cedido)
Tottenham
High: Marcel Lavinier
Low: Cameron Carter-Vickers (Bournemouth, cedido), Jack Clarke (Stoke, cedido)
Villarreal
High: Étienne Capoue (Watford), Hassan Haissem, Andrei Rațiu
Low: Soufiane Chakla (Getafe, on loan), Vicente Iborra, Takefusa Kubo (end of loan)
Wolfsberg
High: Gustav Henriksson (Elfsborg), Thorsten Röcher (Ingolstadt)
Low: Marc Andre Schmerböck (Hartberg), Marko Soldo
Young Boys
High: none
Low: Nicolas Bürgy (Paderborn, loan), Léo Seydoux (Westerlo), Taulant Seferi (KF Tirana, loan)