Clark Robertson, Ryan Tunnicliffe and Louis Thompson could all return to Pompey's matchday squad at Exeter on Friday after time out injured.
They may all feature as manager Danny Cowley looks to rotate his squad now they are back in action after their three-week Covid-enforced break.
Cowley told the club website 'They are all back training with us and have now had a good few days into their legs, which is a real positive. Clark and Ryan were both long-term injuries, so they do almost feel like new signings for us. It’s great to have the three of them back.
'There are also no fresh injury concerns off the back of Cambridge and no new Covid illnesses to report.'
Cowley is happy to be in action again four days after the 0-0 draw at Cambridge, which did reveal a little rustiness from some. He told the site: 'It’s a game that’s come at a really good time for us and gives us the opportunity to get more minutes into players’ legs.
'We’ll look for everyone that didn’t play at Cambridge to get some time on the pitch and are searching for the right balance. If we can find that and then navigate our way through on Friday, then it gives us another tie on Tuesday.
'They would be two useful preparation games for what is going to be an incredibly intense league schedule. But Exeter are a strong team and I had the pleasure of watching them at Forest Green in the league on Tuesday.
'They’ve got plenty of depth in their squad and some really promising young players, with a nice blend.'
The winners of Exeter-Pompey will visit Cambridge in the last 16 next week with the vicotrs from that tie off to Rotherham in the quarters.