Arvin Appiah scored the winner deep into stoppage time as Nottingham Forest Under-23s made it two wins from two at the expense of Crystal Palace.
Gerry McDonagh had given Forest a 20th minute lead at Selhurst Park before Palace levelled close to the hour mark, only for Under-18s forward Appiah to step off the bench and claim the points.
Forest did not field a single senior player in the Professional Development League match, whereas Palace named veteran defender Damien Delaney and left-back Pape Souare, who was playing his first match in a year after a serious car crash.
McDonagh opened the scoring with his second of the season, after beating goalkeeper Dion-Curtis Henry to the ball and scrambling it home.
Palace, who had won their first two matches of the season, then had two goals ruled out before McDonagh missed a chance to double the lead.
Freddie Ladapo hit the post for the hosts early in the second half, but he was not to be denied when he turned his man and beat Liam Bossin in the 62nd minute.
Palace might have gone on to win it when Levi Lumeka became the second man to hit the post for the Eagles.