For seven years Pompey occupied the top flight, consisting of two top-nine finishes, the FA Cup, and notable Fratton Park victories over Liverpool, Manchester United, Spurs, Manchester City and Leeds among others.
However, Williamson will be regarded as one of the more curious signings following his £3m arrival from Watford in September 2009.
For the central defender never played a match – before sold off to Newcastle just five months later.
Recruited under manager Paul Hart, the closest Williamson ever got to the first-team was as an unused substitute on seven occasions.
Strangely, he wasn’t even handed an outing in any of the cup competitions either, failing to make three Carling Cup squads entirely.
When there was a necessary change of manager in November 2009, with Avram Grant replacing Hart, it made absolutely no difference to the defender’s dormant playing chances.
Instead he was shipped out to Newcastle in January 2010 for an undisclosed fee, where he helped them to promotion to the Premier League during his opening six months.
A successful St James Park stay saw him feature 170 times and score twice over the next six years, albeit hampered by injury.
Williamson would later turn out for Wolves and Oxford United, before dropping into non-league in August 2018 with Gateshead.
On Bank Holiday Monday, he marked his third season as their player-manager by taking The Heed back into the National League following a 2-2 draw at Chorley.
During the campaign, Williamson turned out 22 times, netting once, despite his 39th birthday looming later this year.
Promotion was particularly sweet for Gateshead, who were thrown out of the National League and relegated to National League North in June 2019 for ‘multiple breaches’ of financial rules.
At the centre of the controversy was owner Dr Ranjan Varghese and his advisor Joseph Cala, with the latter perhaps familiar to Pompey fans.
The American-based business was associated with underwater casinos when, in January 2012, he declared an interest in buying the Blues during their financial problems.
Ultimately, Gateshead came within 72 hours of going out of business before resurrected by a supporter-led consortium, with Williamson installed as manager.
And next season the Pompey player who never played will be overseeing a National League side once more.
A message from the Editor, Mark Waldron
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