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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1. Amdy Faye
One of the most famous triallists as Harry Redknapp concocted a story about misunderstanding the Frenchman talking about Thierry Henry and thus calling him Andy Henry on the team sheet at Kilmarnock in 2003. Photo: Phil Cole
2. Geovanni
Pompey had the Barcelona man in their grasp before Manchester City snatched him away Photo: Daniel Hambury
3. Eugen Bopp
Famously, or infamously, around under Paul Hart in 2009 but never made an appearance Photo: Robin Jones
4. Thiago Motta
Another huge name who was at the club's Eastleigh training ground early on his career Photo: Dean Mouhtaropoulos