Dion Donohue revealed he turned down a Pompey stay after agreeing a move to Mansfield.
Donohue explained a desire to be nearer his north Wales home was a significant factor in his exit as he searches for regular minutes.
He told mansfieldtown.net: ‘I had glandular fever towards the start of pre-season, which is not a nice thing to have.
‘I think that had a knock-on effect, as in I was trying to catch everyone up and rush back. Every time I came back, I went straight back into the team.
‘Obviously I want to play as much as possible, but at times I think I tried to do a bit too much. Thankfully, I’m over that now, and I’m raring to go.
‘They (Pompey) had an option of (extending my contract for) a further 12 months. I had a conversation with the manager, and he said he wanted to take it up.
‘I asked him if he’d rather not take it up, because I wanted to move closer to home and I think I needed a fresh start to re-energise myself and give myself something to get excited for.’