UEFA Europa League – Round of 16 (Second Leg)

15 March 2011
Olympiacos – Metalist Kharkov

Referee: Ovidiu Hategan (ROU, photo)
Assistant Referee 1: Zoltan Skekely (ROU)
Assistant Referee 2: Octavian Sovre (ROU)
Additional AR 1: Alexandru Tudor (ROU)
Additional AR 2: Cristian Balaj (ROU)
Fourth Official: Sebastian Coltescu (ROU)

Manchester City – Sporting Lisbon
Referee: Tom Harald Hagen (NOR)
Assistant Referee 1: Dag Nebben (NOR)
Assistant Referee 2: Frank Andas (NOR)
Additional AR 1: Tommy Skjerven (NOR)
Additional AR 2: Espen Berntsen (NOR)
Fourth Official: Brage Sandmoen (NOR)

Hannover – Standard Liege

Referee: Pavel Kralovec (CZE)
Assistant Referee 1: Martin Wilczek (CZE)
Assistant Referee 2: Antonin Kordula (CZE)
Additional AR 1: Miroslav Zelinka (CZE)
Additional AR 2: Radek Prihoda (CZE)
Fourth Official: Libor Kovarik (CZE)

PSV Eindhoven – Valencia CF

Referee: William Collum (SCO)
Assistant Referee 1: Derek Rose (SCO)
Assistant Referee 2: Martin Cryans (SCO)
Additional AR 1: Alan Muir (SCO)
Additional AR 2: Robert Madden (SCO)
Fourth Official: Allan Crawford (SCO)

Athletic Bilbao – Manchester United

Referee: Cuneyt Cakir (TUR)
Assistant Referee 1: Tarik Ongun (TUR)
Assistant Referee 2: Emre Eyisoy (TUR)
Additional AR 1: Huseyin Gocek (TUR)
Additional AR 2: Bulent Yildirim (TUR)
Fourth Official: Suleyman Abay (TUR)

Udinese – AZ Alkmaar

Referee: Milorad Mazic (SRB)
Assistant Referee 1: Milovan Ristic (SRB)
Assistant Referee 2: Igor Radojcic (SRB)
Additional AR 1: Vlado Glodjovic (SRB)
Additional AR 2: Milenko Vukadinovic (SRB)
Fourth Official: Bosko Jovanetic (SRB)

FC Schalke – FC Twente

Referee: Viktor Kassai (HUN)
Assistant Referee 1: Gyorgy Ring (HUN)
Assistant Referee 2: Robert Kispal (HUN)
Additional AR 1: Istvan Vad (HUN)
Additional AR 2: Tamas Bognar (HUN)
Fourth Official: Mihaly Fabian (HUN)

Besiktas Istanbul – Atletico Madrid

Referee: Paolo Tagliavento (ITA)
Assistant Referee 1: Massimiliano Grilli (ITA)
Assistant Referee 2: Gianluca Cariolato (ITA)
Additional AR 1: Christian Brighi (ITA)
Additional AR 2: Gabriele Gava (ITA)
Fourth Official: Antonio Damato (ITA)