Kilmarnock under Lee Clark - made his debut for his hometown club two years ago. And he made a name for himself when he scored a spectacular goal against Manchester United during his debut season.
Stephen Glass, who had a spell at Newcastle United as a player after leaving Pittodrie, is delighted to add England Under-20 international Longstaff to his ranks after also signing Marley Watkins.
He told the Dons website: “For a young player, Matty has already played in a good number of high-profile games for a top club, against some of the biggest teams in England.“We believe he is going to continue to make good progress here with us.
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