The clash with the Lions will be Guaita's first of the pre-season, while Meyer featured against Oxford United and Schlupp has appeared in both games so far.
The trio replace Wayne Hennessey, Andros Townsend and Eberechi Eze in the Palace lineup. All three of the replaced players are not in the squad today, with Eze and Hennessey called-up to international duty.
This leaves the Eagles with a very youthful bench, including teenagers Malachi Boateng, John-Kymani Gordon and Brandon Pierrick. All three of these promising youngsters have featured with the first-team in both of the last two friendlies.
New Millwall arrivals Scott Malone and Mason Bennett both start, having joined from Derby County at the end of last week.
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Millwall: Bialkowski, Hutchinson, Cooper, Williams, Wallace, Bradshaw, Malone, Pearce, Leonard, Bennett, Muller.
Subs: Sandford, Wright, Brown, Tiensia, Wallace, Woods, Thompson, Mahoney, Burey, Smith, Skalak.
Palace: Guaita, Ward, Kouyaté, Dann, Mitchell, Schlupp, Riedewald, McArthur, Meyer, Zaha, Ayew.
Subs: Henderson, Kelly, Woods, Jach, Malachi Boateng, Inniss, Kirby, Gordon, Pierrick.