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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17. Frederic Brando
Former Marseille man was at Pompey in 2003 - giving Harry Redknapp a chance to pepper his post-match interview with Marlon Brando quotes to an oblivious press Photo: Shaun Botterill
18. Denilson
Pompey handed Brazilian winger Denilson a trial in 2006. The one-time world's most expensive player when he signed for Real Betis for £21.5m, couldn't agree a deal with the club Photo: RICARDO MAZALAN