Steven Schumacher has confirmed that James Bolton will not be ready for the start of the new season after another Plymouth Argyle defender, Brendan Galloway, made his return to action after eight months out.
Bolton is 'progressing fine' after suffering a broken bone in his left foot during the away League One game against Ipswich Town in March but has not started any ball work yet.
The 27-year-old will not be ready for the season-opening game against Barnsley at Home Park on Saturday, July 30 but Schumacher is confident that Bolton 'won't be too long' after that.
Galloway played for the first time since last November when he made his comeback from a serious knee injury as a 72nd minute substitute in the 1-0 defeat by Bristol City on Saturday.
The Zimbabwe international will get more game time, probably as a substitute again, in the away pre-season games against Torquay United tomorrow night and Yeovil Town on Saturday.
On Bolton, Schumacher told Plymouth Live: "He's not involved with the balls or anything yet so, realistically, he will not be ready for the very start of the season.
"He's progressing fine but he's not in any sort of ball work or contact work yet. It's just small steps with him and two weeks isn't going to be enough for him to be ready for the first game, but I'm sure he won't be too long.
"The transfer window doesn't shut until September 1 so if Bolts isn't right and we don't think he's going to be right for then, hopefully we will have enough left in the budget to bring in cover if and when needed."
With Bolton still out, the return of Galloway will add to the defensive options for Schumacher, who has James Wilson, Dan Scarr and Macaulay Gillesphey available to him at the moment, plus teenage duo Oscar Halls and Brandon Pursall.
Schumacher said: "I'm made up to have Brendan back. He has been out for so long, he has been on a real tough journey to come back from a major injury.
"He's a great lad, a great professional and I'm so pleased to have him back involved. Obviously, he's going to need more minutes, going to need more game time, more training sessions.
"He will just go from strength to strength now. Coming on the pitch, that's the first barrier you have got to get over and thankfully he has done it.
After such a lengthy absence, Argyle will be patient with Galloway and give him plenty of time to get back to full fitness.
Schumacher said: "Everything will just become more natural. When you have been out for so long it feels like your boots on the wrong feet. He did look a little bit rusty (against Bristol City) but that's just to expected, everyone does that.
"He will have been made up to get some minutes, he will get some more minutes next week and then the Truro game, hopefully, will be a good opportunity for him to get a 90 in. It's all going in the right direction.
"He's experienced enough to know that it's a long process coming back from injuries. He has had enough injuries in his career to understand how it works.
"He knows there is no rush for him to be knocking on the door saying 'Why aren't I playing?' First and foremost he has just to get himself physically right.
"He's doing well, the medical team have looked after him great and he has put the work in himself. He will be ready when he's ready."
Midfielder Panutche Camara also returned from injury as a 60th minute substitute against Bristol City, and with Schumacher bringing in Finn Azaz and Bali Mumba last week on season-long loans from Aston Villa and Norwich City respectively the Argyle squad has now been strengthened considerably.
Schumacher said: "It's really important because going into a tough League One campaign you need people that you can rely on, people that when someone has got a niggle or a dip in form they are ready to step up.
"Having as many fit and available players who can help the team at your disposal is invaluable. I think we are building a good squad, we have got two more injured lads to come back (Bolton and Conor Grant) which will make us stronger.
"Hopefully, we will have one, maybe two more, in the door and that will make us even stronger again."