Arsenal midfielder Fredrik Ljungberg is to see a neurologist after missing the last two games due to migraines, the English Premier League champions said on Tuesday.
Arsenal would not give further details about the condition of the Swedish international, who missed Sunday's 2-2 draw with Chelsea after a recurrence of the migraine that ruled him of last week's Champions League win over Rosenborg Trondheim.
Ljungberg is unlikely to play in Sunday's league match at Portsmouth, the club said.
Speaking after the Chelsea game, Wenger told Arsenal's website: "He had a sudden resurgence of his migraine and we had to send him back home. The doctor said we have to keep him out of training for at least four or five days."