The left-back was tipped to start at left wing-back in a weakened defence for Arsenal against Chelsea this afternoon.
But the 27-year-old was not named in the starting line-up or on the bench by Arsene Wenger.
Gibbs' absence means a start for Alex Oxlade-Chamberlain on the left side.
He said: "We lost three centre-backs in one week.
"Last night we lost Kieran Gibbs who had to go home sick so the decision was not so difficult because we don't have many defenders left."
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Arsenal defender Kieran Gibbs is injured
Last night we lost Kieran Gibbs who had to go home sick
Arsenal's injury woes means no recognised defender has been picked on the bench although midfielder Francis Coquelin has filled in on occasion.
Per Mertesacker leads the team on his first start in 13 months.
The German World Cup will play alongside the inexperienced Rob Holding and Nacho Monreal.
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David Ospina starts in goal in place of Petr Cech, who his understood to be disappointed at being left out of the team by Wenger.
Arsenal: Ospina, Holding, Mertesacker, Monreal, Bellerin, Ramsey, Xhaka, Oxlade-Chamberlain, Alexis, Ozil, Welbeck