By Grey Whitebloom How long can Scott McTominay remain Manchester United’s ‘unlikely’ hero? The divisive midfielder emerged from the bench to head in an 86th-minute winner against Aston Villa on Sunday afternoon, reigniting United’s ambitions of Champions League qualification. McTominay’s seventh league goal of the season – a figure unrivalled among United’s squad – closed the gap to fifth-placed Villa to just five points with 14 games of the campaign remaining. Tottenham Hotspur are only one point better off but a spot inside the top five may be enough to qualify for Europe’s premier club com…