ARSENAL have had an opening £15million bid for Kieran Tierney thrown out by Celtic.

The Hoops have made it clear to the Europa League finalists that their valuation of the 22-year-old left-back is nowhere near enough.

2 Tierney in action for Celtic against Livingston Credit: Kenny Ramsay - The Sun Glasgow

SunSport understands Celts, if they were to sell, would be looking at a minimum of £25m.

London sources expect Arsenal to try again with an improved bid within days. They’ve already tried to tempt the Hoops by including in their offer a choice of fringe players such as Carl Jenkinson, Jordi Osei-Tutu, Emile Smith Rowe or Eddie Nketiah.

The Eight-in-a-Row champions ARE open to the possibility of taking a defender or striker from the Gunners — but only if the fee for Tierney is right.

SunSport revealed that Italian giants Napoli have also enquired about the Scotland ace who has already won three Trebles among eight honours, made over 150 appearances and won 12 caps.

2 Tierney with the Scottish Premiership title at Parkhead Credit: Kenny Ramsay - The Sun Glasgow

Boss Carlo Ancelotti is ready to fight the Gunners for Tierney and it’s believed last season’s Serie A runners-up have asked to be kept informed.

Tierney’s under contract at Parkhead until 2023 and currently recovering from a double hernia op.

The academy graduate may have to consider if he’s achieved all he can in Paradise — and if he has to seek a move to take his career on to another level.

For Celtic chiefs, however, there’s also potentially a need to consider if cashing in their outstanding full-back makes business sense, especially after an injury-hit campaign which saw Tierney restricted to 43 games for club and country.

For now, though, they’re not exactly pushing Tierney out the door.

Boss Neil Lennon conceded he’s anticipating keen interest in Tierney plus midfielder Olivier Ntcham who is interesting Lyon, Marseille and Porto.

On the duo, he said: “I would expect bids. We’re realistic and I’d be surprised if there weren’t any offers for them, put it that way, because they’re both extremely talented players.

“So I may have a decision to make.

“But there’s been nothing for us to think about yet. For someone so young, Kieran already has vast experience — he’s played Champions League, Europa League, internationals and he’s won trophies.

“I don’t think he would fear going anywhere.

“But, personally, it would be a wrench for him because the club means so much to him.

“However, we’ll cross that bridge if and when we come to it — but we don’t want to lose him.”

Meanwhile, David Turnbull went through a stringent Celtic medical in Manchester.

The Motherwell midfielder was forced to travel south due to Scottish facilities being unavailable.

Barring any late hitch, Turnbull will finally complete his £3.25million Hoops switch today.

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