Complex sentence: However, work permit regulations meant that it was not possible for Mamam to play in the United Kingdom and he was sent on loan to play at Royal Antwerp until he was eligible for a Belgian passport.
Split into simpler sentences: However, work permit regulations meant that it was not possible for Mamam to play in the United Kingdom. Mamam was therefore sent on loan to play at Royal Antwerp until he was eligible for a Belgian passport.