The American wing-back has only pulled on a PNE shirt once, for 45 minutes against St Johnstone in July.
He damaged a ligament in the area near his ankle and Achilles in that pre-season friendly and frustratingly has been sidelined ever since.
Olosunde had started running in the last few days and the next step will be for him to join in full training with the first-team squad.
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PNE head coach Frankie McAvoy said: “Matthew is back on the grass running.
“That is progress, he’s had a few days running.
“Hopefully he will be up to speed shortly and we can get him into full training.
“Matthew got the injury at St Johnstone when we were up in Scotland. It’s a nick on the ligament or tendon next to the Achilles.
“They take a bit of time to get right we need to make sure we are careful with him.
“With the bad luck we had with Izzy Brown’s injury, we don’t want lightening to strike twice. It’s a different type of injury but we don’t want to take any risks.”
Olosunde, 23, was signed on a Bosman on the last day of June after turning down a new contract at Rotherham.
He was brought in to play at right wing-back or right-back, with his pace a real attraction.
While Olosunde has sat on the sidelines waiting to recover, Sepp van den Berg has made the wing-back position his own.
McAvoy is delighted with how the Liverpool loanee has done there, so too Josh Earl on the other side of the pitch.
“Sepp has been excellent, he really has,” said McAvoy.
“Last season when we changed the system and put him at wing-back, he did really well there.
“He’s a centre-back by trade but he has all the attributes to play at wing-back – energy, legs, enthusiasm.
“Sepp can be a threat when he gets into the other box, he did it a few times at Bristol City at the weekend.
“At 19-years-old he has hit the ground running this season, I’m delighted with him. Josh Earl has been excellent on the other side.
“He’s had a tough couple of seasons, been out on loan, had spells when he was flavour of the month and then not flavour of the month.
“Josh has had to come back in, find his way, and I think he’s done great – credit to him.
“He’s really athletic and energetic, he’s a good size.
“I hope this is a big season for Josh, I always say to players their destiny is in their own hands and they have the platform to play.
“Josh has so far taken his opportunity and hopefully can continue to progress.”
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