Arsenal’s £25m offer for Kieran Tierney includes too many add-ons and is dependent on them qualifying for the Champions League, something Celtic are not convinced is realistic, Sky Sports News understands.
The Gunners' initial offer of £15m for the left-back was swiftly rejected by the Scottish champions, who then came back with a structured bid in the region of £25m, which was also rebuffed.
Arsenal have previously insisted they remain confident they can get a deal across the line but Celtic are understood to want a simplified deal with more cash up front.
Tierney, who is under contract at Celtic Park until 2023, has played 180 times for the club since becoming a regular in the side in the 2015/16 season.
The 22-year-old was restricted to 21 league appearances for the Hoops last season due to a hernia problem and is currently recovering from surgery.
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