The defender has been out of action with a hamstring injury but trained with the Gunners’ first-team on Monday morning before jetting off to the principality with the rest of the Arsenal squad.
And speaking at his pre-match news conference at the Stade Louis II on Monday night, Wenger confirmed that Gabriel is back in his squad.
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The Gunners boss also revealed that midfielder Tomas Rosicky misses out due to illness, while Chuba Akpom and Alex Oxlade-Chamberlain have also not travelled with the north London side – but other than that it is the same squad that faced West Ham on Saturday.
Oxlade-Chamberlain has been ruled out for around three weeks after suffering a hamstring injury during the 2-1 FA Cup win over Manchester United last Monday.
Arsenal head to Monaco looking to overturn a 3-1 first-leg deficit and reach the Champions League quarter-finals.
“Statistics are against us,” Wenger told reporters on Monday. “But we must do everything to make sure the statistics lie.”
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