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Former Celtic left-back Kieran Tierney has revealed that leaving the Hoops was the hardest decision of his life, as reported on Talksport.
The full-back left during the summer window to join Premier League side Arsenal.

The Scottish international had been with the Glasgow club since his youth days and graduated from the Academy.
He said:
It was a great feeling for me, but it was the hardest decision of my life as well to leave the club I had been at for 15 years. It is a massive change for me.
I was a home boy, I always stayed with my parents, and I’ve come down here to a different country, a massive city.
But so far everybody at the club has helped me settle and I am very grateful for that.
Are Celtic missing him?
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Remarkably, no. It was expected that Tierney leaving would punch a huge hole into the Celtic team.
However, summer arrival Boli Bolingoli has settled in excellently at left-back and arguably had his best game in a Celtic shirt on Thursday night in the Europa League victory over Cluj.
Tierney is still a big Celtic fan and always speaks highly of the club that gave him the platform to showcase his talents.