Complex sentence: Colin Hendry took over as manager in Mangan's third year at the club, and Mangan found it hard to break in to the first team with Hendry's preference of players to be six foot plus, Mangan was therefore released towards the end of the season.
Split into simpler sentences: Colin Hendry took over as manager in Mangan's third year at the club, and mangan found it hard to break in. With Hendry's preference of players to be six foot plus, Mangan was therefore released towards the end of the season.