Former Arsenal midfielder Jack Wilshere admits Kieran Tierney's pace has surprised him in training.

Wilshere has returned to his former team as an unregistered player as he looks to regain an element of fitness to continue his playing career, as well as build up a level of coaching experience.

"We were doing a sprint test today," Wilshere explained to Football.London

"I asked the fitness guy 'who is the fastest player, is it Aubameyang?' and he said 'no it's Kieran Tierney' - it surprised me."

Wilshere has been a free agent since being released by Championship side Bournemouth at the end of last season.