Pompey have signed defender Sean Raggett on a two-year deal.
The 26-year-old centre-back scored two goals in 38 appearances during a loan spell at Fratton Park last season.
He was the last Blues player to find the net before the league was suspended in March, scoring in a 2-2 draw with Fleetwood.
Raggett said: “I spoke to the gaffer a few times. It was an obvious conversation because everyone knows promotion’s the goal and he wanted me to be a part of that.
“I enjoyed working with him and all the boys last season, so I’m delighted to be coming back to the club.
“We were a bit unlucky last season and so now we’re looking forward to getting back and pushing for success again.
"It was an obvious conversation because everyone knows promotion’s the goal and he wanted me to be a part of that."
“I’m excited by the challenge and believe that we’ll be right up there – that’s certainly the aim for everyone.
“When you compare how I am now to the start of last season, then I feel so much better. I’m fit, raring to go and eager to improve my own performances.
“The fans are so loud at the games and we obviously miss them when they’re not there, so I can’t wait for them to be back again when it’s safe.”
Blues boss Kenny Jackett added: “It took Sean a while to get over the injury he had at the start of last season, but he improved greatly as we progressed and I think there’s more of that to come.”