The Northern Irish international makes his third league start of the season but earned rave reviews on international duty earlier this month in a World Cup qualifying win over Luxembourg.
Duffy was part of a backline that shipped four goals in Clement’s debut 4-1 defeat at Birmingham on Saturday.
City goalscorer at St Andrew’s, Mathias Kvistgaarden, drops out of the XI with Emi Marcondes rewarded for an eyecatching cameo in the West Midlands.
Clement pledged to make changes from his Championship weekend bow in the middle of a three-game week cycle.
The Belgian reported no fresh fitness issues from those on duty at St Andrew’s when he previewed Oxford’s visit at Colney on Monday.
Matej Jurasek returns to the bench after he missed out in the West Midlands with what Clement indicated afterwards was illness.
Clement also confirmed on Monday City’s longer term injury absentees will again not be in contention this week.
Full list: Jeffrey Schlupp, Lucien Mahovo, Ben Chrisene, Jose Cordoba, Anis Ben Slimane, Liam Gibbs, Gabe Forsyth, Papa Amadou Diallo and Ante Crnac.
Norwich City: Kovacevic, Stacey, McConville, Darling, Fisher, Topic, McLean, Makama, Marcondes, Schwartau, Sargent. Subs: Grimshaw, Duffy, Medic, Wright, Mattsson, Forson, Jurasek, Mundle-Smith, Kvistgaarden.
Oxford United: Cumming, Long, Brown, Vaulks, Helik, M Harris, L Harris, De Keersmaecker, Goodrham, Ter Avest, Currie. Subs: Ingram, Placheta, Romeny, Prelec, Mills, Leigh, Lankshear, Davies, Krastev.
Referee: Tom Reeves
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