William Sergio Mejia Castillo (born 21 April 1999) is a Mexican professional footballer who plays as a midfielder for Liga MX club Atletico San Luis on loan from Monterrey.
Albania
Algeria
Australia
Belgium
Brazil
Costa Rica
Cyprus
Egypt
El Salvador
England
France
Friendly Games
Ghana
Greece
Hong Kong
India
Indonesia
Iran
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Israel
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Jordan
Kenya
Malta
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Portugal
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Manchester City 
Everton 
Nottingham Forest 
Tottenham 
Wolverhampton 
Celtic 
ST Johnstone 
Motherwell 
Rangers 
Juventus 
Fiorentina 
West Ham 
Liverpool 
Sampdoria 
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AC Milan 
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Benfica 
Ipswich 
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Manchester Utd 
Newcastle 
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Arsenal 
Inter 
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Nacional 
FC Porto 
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Real Madrid 
Aston Villa 
Bournemouth 
Crystal Palace 
Almeria 
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SC Braga