But moments after Glasner had made a triple change for Palace, the Swedish forward was not to be denied; the Eagles ceded possession too close to their own box, and Isak swept home a precise low finish for Newcastle’s fifth goal.
The Eagles’ first real chance of the half arrived on 62 minutes as Mitchell’s high cross found Muñoz unmarked at the far post – but a crowd of bodies on the line saw the Colombian’s header bounce away from danger.
In the closing stages there was one final opportunity for Palace, substitute Adam Wharton pouncing on a loose backpass – but the midfielder could not find fellow substitute Eddie Nketiah, who then had another effort kept out by the imposing frame of Pope.
Newcastle: Pope (GK), Trippier (Krafth, 79), Schar, Burn, Livramento, Guimaraes (Longstaff, 72), Tonali, Joelinton (Willock, 62), Murphy (Gordon, 72), Isak (Wilson, 72), Barnes.
Subs: Dubravka (GK), Targett, Osula, Miley.
Palace: Henderson (GK), Richards, Lacroix, Guéhi, Muñoz, Lerma (Devenny, 85), Hughes (Wharton, 57), Mitchell, Sarr (Esse, 76), Eze (Kamada, 57), Mateta (Nketiah, 57).
Subs: Turner (GK), Clyne, Chilwell, França, Nketiah.
As It Happened