Captain Seán Grehan picked out Umolu with a throw-in and the striker did well to hold off his man and get a shot away that was just inches wide of the mark.
It wasn’t to be for Powell and his Eagles in the north East, with the referee bringing an end to proceedings after six minutes of time added on.
The result means Palace slip to 11th in the Premier League 2 - level on points with Everton and a single point behind the likes of Arsenal and Manchester United with a game in hand.
**Newcastle:** Harris (GK), Shahar, Targett (Hefferman, 60), Hernes, McArthur, Murphy (Charlton, 60), Sanusi, L. Miley (Donaldson, 79), Parkinson, Turner-Cooke, Emerson (Harrison, 78).
Sub not used: Anderson (GK).
**Palace:** Moulden (GK), Cardines, Jemide, Browne (Gibbard, 85), Sheridan, Grehan, Raymond (Grante, 73), Mustapha, Umolu, Derry (Reid, 63), Marsh.
Subs not used: Izquierdo (GK), Austin.