Mahlon Romeo was the 14th – and final – player through the door at Pompey this summer.
The defender completed a season-long loan switch from Championship side Millwall on deadline day.
That came after he impressed against the Blues in a Carabao Cup clash at The Den earlier that month.
And Romeo believes the performance of his new side that night showed that they can have a successful season.
He said: “I’m happy that I’ve got an opportunity at such a big club and ready to be back enjoying my football.
“I’ve loved the majority of the time that I’ve been at Millwall, but feel it’s a good time for me to part ways.
"I’m happy that I’ve got an opportunity at such a big club and ready to be back enjoying my football."
“I wish the club all the best and they’ll always have a place in my heart – especially the two managers I had there, as well as the players and staff.
“If you look at the team here then a lot of them have played in the Championship, so I’m looking to gel with everyone.
“It felt like a normal league game (in the Carabao Cup) and the tempo was high. It was really tough for us.”
Romeo will now be competing with fellow recent arrival Kieron Freeman for the Pompey right-back slot.
He said: “Without boasting, I like to be attacking and on the front foot, getting on the front foot and start counters.
“It’s a really long season and football’s a marathon, so everyone in the squad is going to get their chance.”