Reading manager Brian McDermott must decide whether to recall Danny Guthrie after the midfielder was left out of the squad that drew 3-3 with Fulham at the weekend.
Noel Hunt could replace Jason Roberts, while Hal Robson-Kanu, who came off the bench to score Reading's last-minute equaliser on Saturday, could replace winger Jimmy Kebe.
Arsenal boss Arsene Wenger is expected to ring the changes to his Arsenal starting lineup after the Gunners beat Queens Park Rangers 1-0 on Saturday.
Jack Wilshere will be rested after returning to first-team action at the weekend, while there is expected to be a rare start for Andrey Arshavin.
Carl Jenkinson could return to the side after being dropped to the bench on Saturday and midfielder Emmanuel Frimpong could return from a knee injury.
Recent form
Reading: LWDDLD
Arsenal: LWWLLW
Possible starting lineups:
Reading: Federici; Shorey, Mariappa, Gorkss, Cummings; Leigertwood, McAnuff, Robson-Kanu, Guthrie; Pogrebnyak, Hunt
Arsenal: Martinez; Jenkinson, Djourou, Angha, Miquel; Walcott, Frimpong, Coquelin, Arshavin, Yennaris; Chamakh
Sports Mole says: 1-3
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