Former Arsenal and Celtic striker John Hartson believes the former got Kieran Tierney on the cheap.
The Gunners paid 25m for the Scotland international this past summer.
"Arsenal probably got him on the cheap if you look at the fact Manchester United paid 50m for Aaron Wan-Bissaka," he told the Daily Record.
"Also, average players are going for 30m or 40m and Kieran is certainly not average.
"Celtic could have held out for another 5m or so but it is still good money they have banked, especially due to the fact he has come through the ranks and hasn't cost the club a penny.
"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."
