Dutchman makes starting XI just four days after injury scare on international duty, while visitors field a lone striker in Roque Santa Cruz for evening kick-off at the Emirates
The skipper had missed recent games with a hamstring injury but was declared fit enough for a spot on the bench.
Robin van Persie was also on the team sheet, the Dutch striker making the starting line-up despite an injury scare while playing for the Netherlands on Tuesday evening.
Visitors Blackburn fielded Roque Santa Cruz as a lone striker in their XI, with Phil Jones expected to take a place in midfield in his first start since mid-December.
Arsenal entered the match desperate for a victory that would close the eight-point gap on leaders Manchester United, who defeated West Ham 4-2 at Upton Park earlier in the day.
Arsenal: Almunia; Sagna, Squillaci, Koscielny, Clichy; Song, Wilshere, Nasri; Walcott, Van Persie, Arshavin.
Subs: Lehmann, Diaby, Fabregas, Rosicky, Eboue, Chamakh, Bendtner.
Blackburn: Robinson; Salgado, Samba, Nelsen, Olsson; Emerton, J Jones, P Jones, N'Zonzi, Hoilett; Santa Cruz.
Subs: Bunn, Rochina, Dunn, Benjani, Roberts, Hanley, Diouf.