The Gunners suffered a 2-0 loss to Barcelona in the first leg of their Champions League last-16 clash at the Emirates Stadium on Tuesday night.
You can be unlucky one or two years, but not every year
The north London side managed to keep the Champions League holders at bay for 71 minutes before Lionel Messi scored twice in the last 19 minutes.
Arsene Wenger’s side haven’t reached the Champions League quarter-finals since 2010 after losing in the last 16 to Barcelona twice, Bayern Munich, AC Milan and Monaco.
Former Manchester United midfielder Giles insists Arsenal can’t keep blaming their misfortune in the Champions League last-16 draws.
“They’ve been a little bit unlucky. They’ve finished in second place a couple times and they’ve been drawn against Barcelona,” Giles told Newstalk.
“The idea is to win the group stage.
“Ultimately, if you do what they’re doing, you’re not good enough to go through. You can be unlucky one or two years, but not every year.”
The Gunners make the trip to bitter rivals United in the Premier League at Old Trafford on Sunday afternoon.
Arsenal are in third place and two points behind leaders Leicester City after a 2-1 win against the Foxes in their most-recent Premier League game.
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