Harry Redknapp is now aiming to improve his defensive options after the £11million addition of Peter Crouch.
27-year-old Crouch has signed a four-year contract as the FA Cup winners ended their two-month pursuit of the England striker.
Redknapp says he is now happy with his forwards as the South Coast club are set to compete in Europe for the first time in their 120-year history - but is keen to build on last season's cup win and will start by strengthening the side's ageing defence.
Younes Kaboul, 22, has been targeted to reinforce his back four after the Frenchman failed to impress during his first season at Tottenham.
Reading's Nicky Shorey is also a target for Redknapp, as Pompey have just one recognised left-back in Hermann Hreidarsson, but Royals manager Steve Coppell has demanded at least £4million for the England international.
Redknapp said: "We are always looking to improve and we will see where we go - we keep looking around.
"If you are competing in the UEFA Cup as well, there are a lot of matches. We need strength in depth.
"You can end up playing every Thursday and Sunday and players are going to get injured or need a rest at some stage.
"There are a few positions we need strengthening and Peter (Storrie, chief executive) will be seeing what we can do."
Storrie, who successfully negotiated Crouch's return to the South Coast, added: "We have got a very strong squad now but one or two may want to leave.
"We will be having a continuous look at it and see where we can go in the future."