Pompey have picked up some gems after trial periods down the years, but the Blues have also let some players through their grasp who have gone to have monumental careers in the game.
Here’s a list of some of the most famous - and infamous – triallists from the club’s history, along with some names which may catch you by surprise….
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5. Dele Adebola
Looked close to a deal in 2003 ahead of Pompey's first Premier League campaign before ending up at Coventry Photo: David Cannon
6. Gareth Evans
'Wayne Evans' has to be one of the most successful triallists in Pompey's history Photo: Joe Pepler
7. Son Heung-min
Has to be one of the big 'ones that got away' after it came to light Son had a Pompey trial in 2009. Photo: Nick Potts
8. Papa Bouba Diop
Was at Eastleigh in 2004 before Fulham sneaked in and landed the Senegal man Photo: Tony Marshall