FORMER Rangers midfielder Barry Ferguson has warned Arsenal that they must move quickly to tie Kieran Tierney down on a longer deal at the Emirates - or risk losing the 23-year-old to Premier League rivals Manchester City.

The Celtic youth academy graduate moved to the Gunners in 2019 in a £25million deal and has been a standout performer for the London club in that time - so much so that Ferguson reckons the defender will be attracting admiring glances from Europe's heavyweight sides.

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The Ibrox fan favourite has been so impressed with Tierney's performances of late for club and country that he expects some of the continent's big guns to be watching the Scotland internationalist's situation closely.

And Ferguson reckons that Tierney's improvement at Arsenal means he'll be on the radar of some of the continent's biggest clubs this summer.

He told Go Radio: "If I'm Arsenal I'm getting him and tying him down.

"Because if I'm a Manchester City or something, I'm looking at a player like Kieran Tierney - that's how good I think he is.

"I'll be honest with you, I just love everything about Kieran Tierney.

"I think he's gone up a couple of levels since he's made the move.

"I always thought he was a very good player at Celtic.

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"There was no doubt that he was going to move to the Premier League, but he's gone down to Arsenal and gone up a couple of levels.

"As I mentioned before, Arsenal will need to think about getting him tied down on a new contract or the top clubs in England - now, Arsenal are a top club there's no doubt about it but I'm talking Man City, Man United, or even the top clubs in Europe - if he continues to play like that they'll be looking at him, believe me when I say that."