The keeper’s been training with the Blues and Kenny Jackett revealed he looks set to sign third-year scholarship terms.
Seymour will become the second triallist to win a deal, after fellow-stopper Duncan Turnbull penned terms in March.
But before that, there were no less than 15 players who Pompey run the rule over but didn't offer permanent deals. We've looked at where they all are today...
1. Lawrie Wilson
Turned up for Kenny Jackett’s first Pompey training session two years ago after being released from Bolton but was let go after two days. Wilson subsequently moved to Port Vale, before dropping to the National League with Ebbsfleet where he made 30 appearances this season. Photo: Sarah Standing
2. Harry Isted
The Chichester-born keeper trained with Pompey for several days in 2017. He then underwent a trial period at Luton and won himself a contract at Kenilworth Road. Isted hasn’t made his Football League debut yet and is out of contract this summer. Photo: Sarah Standing
3. Mohamed Maouche
The Frenchman arrived on the south coast in 2017 after previously representing Servette, Lausanne-Sport and Tours. The midfielder featured in a Premier League Cup victory over Southend before he joined Oldham. He scored four goals in 35 games this term and is out of contract this summer. Photo: Colin Farmery
4. Thomas Juel-Nielsen
After Pompey ran the rule over the defender in October 2017. He’s since had somewhat of a nomadic career, playing in America and Denmark and is now playing for Gaz Metan Medias in the Romanian top flight. Photo: Colin Farmery