Neil Lennon says Celtic are close to completing the signing of Toulouse defender Christopher Jullien while talks continue with David Turnbull.
Former France U20 defender Jullien will fill the void left at centre-back following Dereck Boyata's switch to Hertha Berlin.
The 26-year-old has made 106 appearances for Toulouse since joining in 2016, having previously played for Auxerre, Freiburg and Dijon.
"He's a player we've identified for a long time, even before my time here," Lennon told Sky Sports News.
"Hopefully we can get that one over the line soon."
Meanwhile, Lennon says Celtic have not been able to get a deal for Turnbull over the line after an issue with his medical.
"There's been a little bit of a hitch with the medical side of things," he said. "Both clubs are still in negotiation."
'Every player has a price'
While Jullien and Turnbull could be among the summer arrivals at Celtic Park, Kieran Tierney continues to be linked with a move away from the Scottish champions.
Sky Sports News understands Celtic rejected a £15m bid from Arsenal for the defender but the Premier League club are expected to return with an improved offer.
"He's coming back from his surgery and is rehabbing," said Lennon of Tierney.
"It can be a little bit unsettling, a lot of us have been in that position before.
"He has a price, every player does. If any team wants to match that then we have a decision to make but until then there's nothing further to say on it really."
Griffiths makes goalscoring return
Lennon was speaking after Celtic beat Austrian amateurs SC Pinkafield 6-1 in their pre-season opener, with Leigh Griffiths marking his return with a goal.
It was Griffiths' first start in seven months and Lennon was encouraged by the 28-year-old's performance.
"It's great that he's back playing, he's worked very hard," said Lennon.
"He's got a bit more to do but is back doing what he does very well. A tap-in, trademark Leigh goal. I'm delighted for him.
"He's had a really tough few months. It's great to see a smile back on his face. He's an important player for us."
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