 The Gills were still in the Fourth Division in 1962 when Barratt was replaced as manager by Freddie Cox , who inherited a team which had just finished 20th in the table . Cox set about fashioning a new team noted for its formidable defensive capabilities . After finishing in 5th place in 1962 – 63 Gillingham went on to gain promotion the following year , winning the only championship in the club 's history . With goalkeeper John Simpson setting a new club record by conceding only 30 goals all season , the team finished level on 60 points with Carlisle United , but with a fractionally better goal average , and so claimed the championship in the tightest finish in Football League history . 
