Aberdeen manager Derek McInnes says midfielder Craig Bryson is desperate to make up for lost time.
The 32-year-old was the Dons’ major summer signing and viewed as the ideal replacement for departing captain Graeme Shinnie.
But the former Derby County player has been restricted to only five appearances for the Dons due to an ankle injury and has not featured since a 1-1 draw with St Johnstone on September 14.
Ahead of Sunday’s visit of Celtic, McInnes said: “If Craig continues to train as he has done this week, then he’ll certainly be available to play a significant part of the game.
“Can he play 90 minutes? That I’m not convinced of.
“But having been out since the St Johnstone game – which is over six weeks now – it might not be the wisest decision to try to force 90 minutes into him.
“I think he is frustrated. He came with that reputation.
“We wanted him to be the one that would not make us miss Graeme Shinnie as much, in terms of that driving force in the team, that dynamic midfield player.
“But we’ve really been without him this season.
“Even when we’ve had him starting games it has been all about trying to work him towards 90 minutes.
“But we are now nearly into November and we’re still not there yet.
“So it has been frustrating for the player, because it’s like any player arriving at a new club: you want to show your influence.
“I’m pretty sure he will in time, but we are just having to be patient with that.
“There is no doubt, I think, that we will be a better team once Craig is fully fit.”
Bryson was an unused substitute in Saturday’s 3-0 victory at Motherwell when a makeshift midfield pairing of Zak Vyner and Greg Leigh impressed for the Dons.
The pair are likely to get the nod to start again in midfield when Scottish Premiership leaders Celtic visit Pittodrie.
He added: “There was an element of risk in playing Zak and Greg in the middle of the park.
“I knew Zak could play there and he was actually pencilled in for it at Ibrox until Andy Considine went down ill.
“Greg was a bit more risky but he took to it unbelievably well – he reminded me of Shinnie with his running power and ability to turn the ball over.
“He probably won more tackles in there last weekend than we have done in a game for a long time.
“Sometimes you just have to take these risks as a manager.
“I had worked with Greg on it during the international break because I thought that’s what I would go with.
“I watched him in training and got more and more sure he was capable of playing in that role.”