Report: Celtic reject Arsenal's 2nd bid for Tierney

Arsenal have failed in their second attempt to sign Kieran Tierney after Celtic rejected a bid believed to be worth £25 million for the Scottish defender, according to David Ornstein and Chris McLaughlin of BBC Sport.

Negotiations between the clubs are reportedly expected to continue despite Celtic turning down an offer that was previously thought to be near their valuation of the 22-year-old, who's said to be eager for a move to the Premier League.

Arsenal's first offer in June was reportedly valued at £15 million. While the second offer was said to be much higher, it apparently included "a series of staggered clauses" that would result in the fee increasing over time if Tierney's move to north London proved successful, according to Keith Jackson of the Daily Record.

If Scottish champions Celtic eventually agree to sell the left-back, they're expected to collect a club-record fee that will eclipse the £19.7 million earned from the sale of Moussa Dembele to Lyon last summer. The transfer fee would also be the most expensive in Scottish football history.

Tierney is currently recovering from a hernia injury that limited him to just 21 appearances last season.