Complex sentence: The team has seen several players selected for Welsh schoolboy rugby and their most notable ex-player is Rowland Phillips, who not only played for first class team Neath, but also played for the Wales national team.
Split into simpler sentences: The team has seen several players selected for Welsh schoolboy rugby. Their most notable ex-player is Rowland Phillips, who not only played for first class team Neath, but also played for the Wales national team.