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Arsenal's Per Mertesacker: We must 'stay cool' at Emirates Stadium
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Arsenal must rediscover missing ingredient before Barca - Mertesacker
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Wenger decision to sacrifice Giroud was as rash as Mertesacker's foul
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Cech better than Courtois and more: What we learnt at Arsenal-Chelsea
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Mertesacker admits: Our chances of going through are now minimal
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Arsenal working 'day and night' to sign players
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Arsenal's Per Mertesacker laments 'worst possible start'
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