Complex sentence: G. David "Dave" Parker is a professional rugby league footballer who played in the 1960s, playing at representative level for Great Britain, and at club level for Oldham, as a, i.e. number 13, during the era of contested scrums.
Split into simpler sentences: G. David "Dave" Parker is a former professional rugby league footballer who played in the 1960s. He played at representative level for Great Britain, and at club level for Oldham, as a, i.e. number 13, during the era of contested scrums.