Shaun Williams revealed that he turned down other clubs in order to become the latest Pompey signing.
The versatile midfielder has put pen to paper on a one-year deal to join Danny Cowley’s Blues revolution.
He arrived with plenty of Championship experience from former club Millwall, where he made almost 300 appearances.
And Williams is hoping that he can now help Pompey make a return to the second tier of English football.
The Republic of Ireland international said: “I’m over the moon. This is such a big club and it’s a privilege to be able to join.
“I was at Millwall for seven-and-a-half year and have unbelievable memories. It’s a great part of my career and something I’ll fondly remember.
"The support base is massive. I know it’s a cliché, but they’ll definitely be a 12th man when they come back to the stadium."
“There were a couple of other options, but this is the one that stood out for me and I’m delighted to get it finalised.
“I’m a composed figure, a team player and I give 110 per cent each week. I just want what’s best for the team.
“Hopefully that means us winning as many games as possible this season and achieving promotion. This club seems to be a bit of a sleeping giant, so we want to be successful.
“The support base is massive. I know it’s a cliché, but they’ll definitely be a 12th man when they come back to the stadium.”
Williams spoke to former Fratton favourites Jed Wallace and Ben Thompson before heading for the south coast.
He said: “Both of them had nothing but good words to say. Jed is still a fan – the first fixture he checks after a game is to see how Pompey got on.
“Ben also had such a successful and enjoyable time here and speaks very highly about the club and the fans.”