They came from Chichester, Bristol, Vienna and Slovakia to attend the Thursday morning event at the X-Bionic Sphere Sports Centre in Šamorín, with some of those attending only visiting the country for 24 hours.
And after the training session, those in attendance were allowed to meet the players for photographs, autographs and, in some cases, a chat.
John Mousinho and sporting director Rich Hughes also took part as fans appreciated the training access granted by the Blues – and here are photographs of all those present...
5. Dean Bowden and Ralph Bowden
Dean Bowden, aged 38 from Chichester, and Ralph Bowden, aged 13 from Chichester, at Pompey's open training session at the X-Bionic Sphere Sports Centre in Šamorín, Slovakia. Photo: None
6. Glyn Tookey and Johann Gangel
Glyn Tookey, aged 56 from Avignon, France, and Johann Gangel, aged 39 from Vienna, Austria, at Pompey's open training session at the X-Bionic Sphere Sports Centre in Šamorín, Slovakia. Photo: None
7. John Mousinho shares a joke with supporters
Pompey's open training session at the X-Bionic Sphere Sports Centre in Šamorín, Slovakia. Photo: None
8. Ben Hardinge, Mercedes Tilling and Arron Corless
Ben Hardinge, aged 36 from Bristol, Mercedes Tilling, aged 34 from Bristol, and Arron Corless, aged 36 from Bromsgrove, at Pompey's open training session at the X-Bionic Sphere Sports Centre in Šamorín, Slovakia. Photo: None