Guillermo Varela Olivera spent time on loan to what reserve team that plays in Segunda Division B?
Guillermo Varela:  He spent time on loan to Spanish club Real Madrid's reserve team, Real Madrid Castilla, and at German club Eintracht Frankfurt, before rejoining Peñarol in 2017. Real Madrid Castilla: Real Madrid Castilla or also known as Real Madrid B is a Spanish football team that plays in Segunda División B.
Real Madrid Castilla