Watkins appeared 12 times for the U21s in the 2013-14 campaign.
The shot-stopper also had a brief loan spell at Tranmere Rovers last term, but didn't make any appearances during his month-long stay with the Merseyside club.
Watkins played a huge role in Villa's triumphant NextGen Series campaign in 2012-13.
He started the quarter-final and semi-final games against Olympiacos and Arsenal respectively before making some crucial saves in the 2-0 final victory over Chelsea.
Watkins has represented England at U16 and U17 level.
Former Villa and Manchester United goalkeeper Peter Schmeichel is his all-time favourite player.