The Blackpool midfielder was due to go under the knife earlier this month after suffering a fractured metatarsal during the Boxing Day defeat to Huddersfield Town.
However, the operation was delayed after Carey - who celebrates his 21st birthday today - tested positive for Covid-19.
Asked for the latest update on Carey’s situation this morning, Blackpool’s head coach told The Gazette: “He had Covid and you then you have to see the specialist again.
“When a player gets Covid, they have to have a heart scan and some other things just to be careful, so we have to wait a little bit longer for Sonny.
“That’s not ideal, obviously. But we will have a decision to make with Sonny because a bone can heal without surgery as well and he’s a young player and his bones are still developing.
“At the moment, we’re just waiting. But that will probably be a decision we make in the next few days.”
Elsewhere, Critchley also revealed the Seasiders have no new injury or Covid concerns ahead of Saturday’s clash against Millwall.
“There’s not a lot of difference to last week to be honest,” Critchley said when quizzed on the latest team news.
“We’ve had no Covid cases this week, no new injuries obviously with not playing at the weekend so we’re in a very similar position to what we were last week squad-wise.”
Chris Maxwell (quad), James Husband (hamstring), Reece James (hamstring), Matty Virtue (ACL), Grant Ward (achilles) and Keshi Anderson (hamstring) all remain sidelined at this moment in time.
On Maxwell, Critchley confirms his return is not “imminent”, although he is progressing well in his recovery from a second quadricep injury of the season.
“He did a little bit of running on the grass the other day for the first time, as he’s obviously just been in the gym doing different types of exercises to build up strength in that part of his body,” he said.
“He’s not imminent, put it that way, so it will be a little period of time yet.
“But him being our captain and an experienced player, we miss him but he’s still a big personality around the training ground and the dressing room on match days.”
On Reece James, Critchley added: “He’s been doing some running this week, just easy straight-line running.
“It’s been three or four weeks for him now, but he’s steadily improving and progressing. When a player steps back out onto the grass, it’s always a positive sign.
“He won’t be ready for this weekend and we’ll see how long it takes him, but that’s good news for us.”
While Blackpool remain low on numbers in central midfield due to injuries to Virtue and Ward and the return of Ryan Wintle to Cardiff City, things have been helped by Ethan Robson’s recall from MK Dons.
The Seasiders could also call upon Kevin Stewart, who is one player who might have benefitted from last week’s postponement of the Barnsley game by getting more time to build up his fitness.
“He’s trained with the group and I think that’s just helped him psychologically because that ankle problem was giving him a bit of an issue,” Critchley said.
“The more sessions he has, the more he has more confidence in his ankle to withstand the load he’s putting it through on a daily basis.
“But so far, so good with Kev.”
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