Now I did not expected that only the missing closing bracket was the problem. But according to OP's comment above it was.
using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(GlobalConfig.CnnString("Tournaments"))
needs to be
using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(GlobalConfig.CnnString("Tournaments")))
Usually such an error will be reported by compiler by "')' expected".
Nevertheless solved.