Jose Mourinho makes just the one change following the slender 1-0 victory at Southampton in the Premier League last weekend, with Eric Bailly dropping to the bench as Smalling returns to partner Phil Jones in the heart of the United defence.
Romelu Lukaku continues to lead the line, with attacking support from Juan Mata, Henrikh Mkhitaryan and Marcus Rashford, while Nemanja Matic and Marouane Fellaini - fit despite ankle problems this week - are in holding midfield roles.
Anthony Martial, who scored in the midweek Champions League victory over CSKA Moscow, is among Mourinho's options on the bench.
For the visitors, Roy Hodgson makes four changes from the side's mauling at the hands of the other half of Manchester last weekend - a result that made it an English top-flight record six defeats without scoring to open the season.
Ruben Loftus-Cheek is also on the treatmenttable , having suffered a thigh injury, so Jason Puncheon earns a recall into the midfield alongside Luka Milivojevic, Yohan Cabaye, Andros Townsend and Jeffrey Schlupp.
Manchester United: De Gea; Valencia, Jones, Smalling, Young; Matic, Fellaini; Mata, Mkhitaryan, Rashford; Lukaku
Subs: Romero, Bailly, Blind, Darmian, Herrera, Lingard, Martial
Crystal Palace: Hennessey; Ward, Sakho, Delaney, Van Aanholt; Townsend, Milivojevic, Cabaye, Schlupp, Puncheon; Sako
Subs: Speroni, Kelly, Riedewald, McArthur, Mutch, Lee, Ladapo
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