Neil Lennon has warned Celtic will not be pushovers in any Kieran Tierney transfer after rejecting a second bid from Arsenal.

Celtic are thought to have set a £25million price tag for the left-back with Arsenal's latest bid reported to have fallen short in terms of the structure of the add-ons.

The Scottish champions have seen Moussa Dembele linked with a huge summer move less than 12 months after selling him for £19million and earlier sold Virgil Van Dijk for an initial £13million before seeing Southampton move him on to Liverpool for five times that price.

So they will stand firm in their valuation of the Scotland international.

Lennon said: "I don't know what Arsenal's financial state is, I know what ours is and we are quite comfortable with the situation at the moment.

"There has been a second bid, the bid has been rejected, and it's as you were.

"Whether they come in again or not, I can't answer that.

"He's a great player and a great talent and at 22 he has already achieved a hell of a lot in his career and has so much more to give to the game.

"It doesn't surprise me there are potential suitors out there for a player of his quality but he's our player, he's on a long-term contract and – while it's a back-handed compliment for all the work people have done here over the years with Kieran – we don't want him to go."

Lennon was asked if Arsenal's bid was disrespectful given Manchester United recently paid Crystal Palace £50million for full-back Aaron Wan-Bissaka.

"Disrespectful is strong but I do feel our valuation of Kieran is correct," Lennon said. "We can't do anything about what clubs do in England. Fifty million for Wan-Bissaka is a lot of money.

"We feel Kieran is a far more experienced and more rounded full-back at this juncture of his career. So he's an asset for us and we rate the player very, very highly.

"We are not going to be pushed over in any negotiations, we are in a strong position in a lot of our assets in the team.

"I mean, some of the players who have left here in the last few years have gone on to do alright in the Premier League, so we think we know what we are doing in terms of developing players.

"Do we believe they can play in the English Premier league? Of course, but we don't want them to play in the Premier League. We want them to play here and in the Champions League for us."

Tierney is still not in contention to play following a double hernia and pelvic problems.

But Lennon said: "He is out on the grass, he is a couple of weeks away from joining in with the rest of the team. It's a slow-burner but we are pleased with the progress he is making."

Another left-back, Boli Bolingoli, has recovered from an ankle injury in time for Wednesday's Champions League qualifier against Sarajevo, with Celtic 3-1 up after the away leg.

Lennon has told his team to be positive ahead of the second leg of the first qualifying round.

"(We need to) go out and try to win the game and don't be complacent, and show Sarajevo the respect we showed them in the first leg," he said.

"It was a good game from our point of view, we played well, and we can't take any opposition lightly in this competition.

"While it's a good lead, it's not over yet. It's another step forward in terms of getting a game under our belt and hopefully we can be sharper and fitter."

Summer signing Christopher Jullien is likely to need more match fitness before making his debut while Mikey Johnston (thigh), Marian Shved (groin) and Vakoun Bayo (hamstring) are just short of comebacks.