4 Markus Merk

Merk, one of the youngest referees in football, began his career at the age of 25. He presided over many games in the Bundesliga and holds the record for officiating the most Bundesliga matches in league history. He received the best FIFA referee award and a record six DFB German Referee of the Year awards for his work as a referee.

He has officiated in many high-profile matches, including the 1997 UEFA Cup Winners Cup Final, the 2003 UEFA Champions League Final, and the 2004 EURO Final.

3 Oscar Ruiz

Ruiz worked as a FIFA-affiliated referee from 1995 to 2011 and established himself as one of the best Referees in Colombian football. He retired in 2011, and then joined Colombia's football referee association.

2 Frank De Bleeckere

From 1998 to 2012, Frank de Bleeckere worked as a FIFA-affiliated referee after making his professional debut in 1984, and he was named Belgian best referee seven times between 2000 and 2013. Bleeckere made his international referee debut in a FIFA World Cup qualifier between Cyprus and Ireland in 2001. In addition, he is the only Belgian referee to have assumed refereeing over seven World Cup games.

1 Pierluigi Collina

Players would have to be brave to argue with Pierluigi Collina, who was both respectful and intimidating as a referee. He did not tolerate malarkey from players, and regardless of the player, he carried out his duties as a referee. In 1996, he officiated the Champions League final between Bayern Munich and Manchester United, as well as the Olympics final men's match between Argentina and Nigeria.