Pompey secured the signing of Marlon Pack earlier in the window as he marked his return to Fratton Park following Cardiff exit at the end of the season.
Meanwhile a deal for former Preston defender Joe Rafferty is also apparently close.
The Blues boss is still requiring plenty of improvement across the pitch with at least three new strikers currently top of his wishlist as well as further strengthening in defence and in goal.
But could Cowley still turn to any free agents currently available in the market this summer?
We’ve taken a look at the top 10 players still without a club following their exits from League One clubs.
Here’s what we found.
5. Tom Carroll
Like Norwood, Ipswich failed to offer the midfielder new terms following the conclusion of his deal. The 30-year-old spent just 12 months with the Tractor Boys where he amassed 17 outings but failed to score or provide an assist during his difficult campaign at Portman Road. Photo: Alex Davidson
6. Oumar Niasse
The former Everton striker found himself in League One with Burton after he signed a deal until the end of the season in February with the Brewers. Despite scoring three goals in 12 outings he was released by Jimmy Floyd Hasselbaink and is yet to be linked with a move elsewhere. Photo: Justin Setterfield
7. Sam Winnall
Winnall was one of four players released by the U’s following the end of their deals last season. However, the 31-year-old has been linked with a move to newly-promoted League Two side Grimsby after a run for just 20 outings in League One last term. Photo: Pete Norton
8. Nathan Delfounso
The former Blackpool man had his ties cut with Botlon at the end of the season after he spent the second-half of the campaign on loan with Bradford. The forward endured a tough two-year stay with the Whites, where he netted 10 times in 57 appearances. Photo: Charlotte Tattersall