Brendan Rodgers has confirmed that neither Cameron Carter-Vickers or Reo Hatate will be involved in this weekend's cup tie against Kilmarnock.
Celtic will make the short journey down the M77 on Sunday afternoon for the Viaplay Cup last-16 encounter.
Carter-Vickers and Hatate both pulled up at Pittodrie last weekend, with hamstring and calf strains respectively.
It's unknown how long either player will be on the sidelines, but they will definitely miss Killie away.
There is also another defensive injury blow in the shape of Stephen Welsh, fresh from signing his new four-year deal at the Scottish champions.
Asked about the contract, Rodgers said: "Yeah, it's great for him. He picked up a little bit of a knock today which is a shame for him considering he's just signed his new deal.
"Really pleased for him. He's a guy that loves Celtic and loves playing here. He's been a great player here within the squad over the last couple of years.
"He's maybe not played as much as what he would've liked, but his heart's very much here and I'm delighted he's committed to signing."
On Carter-Vickers and Hatate, he added: "Obviously, not available for this weekend. We just have to assess them and see how they are over the coming weeks."
Alistair Johnston is back in first-team training at Lennoxtown. He was pictured with his teammates earlier today.
It's believed this game will come too soon for him to play in, so Anthony Ralston will continue his run in the team at right back.
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