Complex sentence: He has worked alongside Mourinho since 2002, a period that had seen the manager and his staff fail to lose a league game at home in 8 years, the run ending with a 0-1 defeat to Sporting Gijón.
Split into simpler sentences: He has worked alongside Mourinho since 2002, a period that had seen the manager and his staff fail to lose a league game at home in 8 years. The run ending with a 0-1 defeat to Sporting Gijón.