Arsenal will be without captain Thierry Henry for tomorrow's Barclays Premiership north London derby with Tottenham Hotspur.
The striker had been struggling with a neck injury, and missed the trip to Bolton last weekend - but further tests have discovered a problem with the sciatic nerve.
Manager Arsene Wenger told reporters this afternoon: 'He was fit against Fulham on Wednesday, but then had the problem on Thursday. 'He will be suspended against Porto next week, so that gives him some time to cure.'
Central defender Philippe Senderos is suspended following his sending-off in the midweek defeat to Fulham, so fellow Swiss international Johan Djourou is likely to come in.
Mathieu Flamini (calf) is out, but Freddie Ljungberg, Gael Clichy, Emmanuel Eboue and Cesc Fabregas are expected to return to the starting XI, while Julio Baptista should also make the squad.
Defender William Gallas (thigh) continues his recovery, with Abou Diaby (ankle) and Lauren (knee) longer-term absentees.
Tottenham skipper Ledley King is expected to be fit despite a suspected virus.
Jermaine Jenas is back in contention after recovering from a calf injury but the derby comes too soon for Paul Stalteri (knee), Mido (groin) and Anthony Gardner (knee).
Hossam Ghaly is suspended as Spurs look to win away against their neighbours for the first time since 1993.
Arsenal squad: Lehmann, Eboue, Toure, Djourou, Clichy, Ljungberg, Fabregas, Gilberto, Hleb, van Persie, Adebayor, Almunia, Walcott, Rosicky, Baptista, Hoyte, Song, Aliadiere
Tottenham squad: Robinson, Cerny, Chimbonda, Dawson, Lee, King, Assou-Ekotto, Davenport, Davids, Huddlestone, Jenas, Ziegler, Murphy, Malbranque, Tainio, Zokora, Lennon, Defoe, Keane, Berbatov.
