Former Celtic centre-back Erik Sviatchenko has defended the club's current pairing at the heart of the defence.
Kris Ajer and Christopher Jullien have received a degree of criticism for recent performances, in particular following the Champions League qualifying defeat to Ferencvaros.
Danish stopper Sviatchenko played for Celtic between 2016 and 2018 as a knee injury cut short his Parkhead career.
He returned to Danish side FC Midtjylland initially on loan before a permanent deal was struck.
Sviatchenko was liked by the Celtic fans despite the reduced number of games he played - and he issued a strong defence of the current crop in his old position.
Speaking on the Go Radio football show, he said: "It's emotional sometimes when fans are giving criticism to the players.
"Because not long ago, a couple of months before the corona, they were doing absolutely brilliant. They were playing away in the Europa League and progressing.
"They could get a lot of praise and then you get a couple of games where they struggle a little and that's natural.
"So in that sense it's a bit harsh to get the criticism that they do because they are good players.
"And they need to have all the games they can have together so I still think the pairing is good, especially with Ajer who is still young and has already played 100 games.
"Some people forget sometimes that he has done so much and with Jullien I see he also has a really good presence about him. I think they have been good, to be fair."
Sviatchenko played a small part in the club's run to Nine In A Row in his two years at Parkhead.
He was part of Brendan Rodgers' treble-winning invincibles side of 2016/17 but left before the second set of domestic honours was completed the following season.
And he insists those memories mean he wouldn't say no if Neil Lennon picked up the phone to ask if he'd like to return.
"It was an experience that I loved every second of and something that I hope I can experience again," he added.
"You never know. If they call, I will always be up for a return.
"Some things happen for a reason and as we talk about, maybe one day I will play at Celtic Park.
"Maybe not in the Hoops jersey, it might be in another jersey."
