John Hartson believes Kieran Tierney will be a great success for Arsenal, claiming he is better defensively than fellow Scottish left back Andy Robertson.

The former Celtic defender moved to Arsenal in August in a £25 million deal but has only managed two appearances for the Gunners because of a double hernia injury.

However, the 22-year-old has already made a strong impression in the Premier League after his performance in Arsenal’s 4-0 Europa League win against Standard Leige and scored the opening goal.

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Concentrating on getting back to full fitness, Tierney pulled out from Steve Clarke’s Scotland squad for the Euro 2020 qualifiers against San Marino and Russia and not risk a setback.

Hartson believes that when the young full-back does fully recover, he’ll be a star signing for the Gunners and is a ‘better defensive player’ than Robertson, according to The Scottish Sun.

He said: "People talk about Andy Robertson. I would say at this moment in time he has better delivery but Kieran is a better defensive player.

"Kieran gets low and defends well and he can also play as wing-back if needed.”

Similar to Tierney, Hartson played for both the Hoops and Arsenal before retiring in 2007.

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"I watched Robertson when he was playing for Dundee United when I was covering the game and he was good.

"He went down to Hull and his career fizzled out there but Liverpool took him and now he is on fire.

"He is worth £25m and he can excel in a different league because there’s a perception the Scottish league is just not as good."

Robertson joined Liverpool from Hull in a long-term deal in July 2017 for an initial fee of £8 million.