The last couple of years have been difficult for the Privett Park outfit.
Financial problems culminated in Borough’s relegation from National League South.
Hook was appointed as John Stimpson’s successor in 2009. During his tenor, Borough reached the FA Trophy final at Wembley.
But Hook steps down as chairman after eight years.
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In a statement, he said: ‘After eight years I have taken the decision to step down as chairman of Gosport Borough FC. I believe now is the right time for me to hand over to someone new.
‘Gosport is a great community club, it is the community spirit and help that makes it what it is.
‘I want to thank all my fellow directors, volunteers, helpers, football management teams and players for their tireless work over the past eight years which has made it such an enjoyable experience for me being the chairman.
‘During that period, there have been many enjoyable times and I am happy the club have progressed both on and off the field.
‘However, in the modern game football is all about finances and we have struggled over the years to bring sufficient funding to maintain the level we were playing in.
‘Every penny raised during my term of office went into the playing budget to give the fans the best possible team we could each year.
‘Recently I have struggled trying to do the job, which has always been done on a voluntary basis.
‘Dealing with football administrators, who do not appear to be helpful towards community clubs, has been very difficult and frustrating and wish my successor well.
‘I know the Southern League will be far more accommodating.
‘During my tenure as chairman many things have happened off the field which has helped take the club forward.
‘We have seen the building of the 328-seat Harry Mizen stand, a new tea hut, club shop, first aid and toilet block. Also, the refurbishment of the old stand and home dressing rooms, the introduction of the veranda outside the recently-refurbished Inn off the Post clubhouse, along with new drainage and irrigation.
‘On the field, I have enjoyed working with only one first-team manager, had a great day at Wembley when we reached the FA Trophy final, reached the first round of the FA Cup and won the Hampshire Senior Cup.
‘We have been unbeaten in the Russell Cotes cup for five years, won the Wyvern Midweek League, the John Stimpson Memorial Shield years and had our largest win in history (19-1).
‘Whether I have been a good chairman, or bad, is not for me to say.
‘The record books will tell their own story. For me, it has been a wonderful time to be associated with the club and I wish it well for the future and for it to go on from strength to strength.’