Career
He appeared 275 times in the Football League for Millwall, Crystal Palace and Portsmouth, before moving into non-league football with Chelmsford City and Hillingdon Borough
Summersby began his playing career at Millwall, initially as a junior before signing as a professional in March 1952, but did not fully establish himself in the first team until 1957. In December 1958, he signed for Crystal Palace then playing in the Fourth Division in its inaugural season. He quickly became a first team regular and put together a sequence of 126 consecutive appearances, many of them alongside Johnny Byrne.
Only Byrne the same season (30), Andrew Johnson in 2003-2004 (28) and Glenn Murray in 2012-2013 (30) have scored more goals.
The next season, Summersby made 42 appearances, scoring 8 times, but in 1962-1963 only appeared 17 times (in the first half of the season) and scored twice. At the end of that season, in May 1963, he transferred to Portsmouth, rejoining former Palace manager George Smith.
However after only 12 games for Portsmouth, over two seasons, Summersby moved on to non–league football with Chelmsford City and later Hillingdon Borough.