Football referees

Ozan Ergün

Oleg Evstigneev

Olsid Ferataj

Oliver Fluch

Oscar Forsberg

Omar Gallo

Oleksii Garkusha

Ondřej Ginzel

Oğuzhan Gökçen

O. Goldrick

Oscar Javier Gómez Flórez

Orel Grinfeeld

Onur Güneş

Oleg Gurchenko

Oleg Gusakov

Ovidiu Alin Hațegan

Oleg Igorevich Zhuravlev

Osama Ismail

O. Jantunen

Oh-Hyeon Jeong

Oscar Johnson

Oleksandr Kalyonov

Orhan Karaboğa

Okan Kayataş

Ola Kellerhals

Omar Khaild

Oleg Kogut

Osman Köksaldı

Oleg Koretskiy

Osiase William Koto

Oleksandr Kovalenko

Orlando Kuka

O. Kwinda

Oliver Langford

Owen Lawrence

Ondřej Lerch

Oliver Lossius

Oliver Mackey

Óscar Maldonado Urey

Óscar Mejía García

Othusitse Modise

Osman Mohammadi

Oscar Moncada

Oliver Moran

Orxan Məmmədov

Odeh Na'al

Ori Nakel

Oshane Nation

Ola Nielsen

Ola Hobber Nilsen