Complex sentence: John Barton is a professional rugby league footballer who played in the 1950s, and 1960s, playing at representative level for Great Britain, and at club level for Leigh and Wigan, as a, i.e. number 8 or 10, during the era of contested scrums.
Split into simpler sentences: John Barton is a former professional rugby league footballer who played in the 1950s, and 1960s. He played at representative level for Great Britain, and at club level for Leigh and Wigan, as a, i.e. number 8 or 10, during the era of contested scrums.