The Northampton Town Football & Education programme South Central Championship squad were edged out 2-1 by their Crystal Palace counterparts in Wednesday's fixture at Moulton.
The visitors started strongly and opened the scoring on 21 minutes, Mountford-Hill looked like he had been fouled but play continued and Palace took the lead with a near post finish.
Jonny Harris came close to a leveller on 35 minutes but his left foot strike was parried away, before a deflected Johnny Carey effort was tipped over.
Callum Law came close early in the second half but after catching the keeper out with a quick 40 yard free kick, the ball struck the post and bounced away to safety.
That proved to be a key moment as the visitors doubled their lead two minutes later, with 55 on the clock.
The Cobblers had a lifeline with nineteen minutes to play when a ball over the top from Douglas was finished by Harris who scored via the cross bar.
Northampton Town battled hard to find a leveller but the visitors held on to claim a narrow win.
Cobblers: Brad Timlin, Zack Douglas, Tyrun Primus, Johnny Carey, Ethan Aldridge, Nico Mountford-Hill, Elliot Balchin-Love, Callum Law, Jonny Harris, James Lewis, Keiron Mobbs. Subs: Harry Francis-Jones, Aiden Bell, Kenny Kwarteng, Jake Webster