Arsenal Rally from Early Deficit to Beat Cologne in 2017 Europa League

Arsenal came from behind to beat Cologne 3-1 at the Emirates Stadium in the UEFA Europa League on Thursday.

Jhon Cordoba struck after nine minutes following a David Ospina error before substitute Sead Kolasinac levelled proceedings three minutes into the second half. Alexis Sanchez's superb solo effort and Hector Bellerin's late strike wrapped up the three points.

Per the Guardian's Amy Lawrence and Nicola Slawson, the match had to be delayed by an hour due to safety concerns after around 20,000 Cologne fans made their way to the game despite an allocation of just 3,000 seats.

The away fans in the stadium contributed to an electric atmosphere, and they quickly had something to cheer after their team took an early lead when Ospina was caught out after a poor clearance, allowing Cordoba to strike from 40 yards with the goalkeeper stranded in no man's land.

The Mirror's John Cross remains unconvinced by Petr Cech's understudy:

Soon after, Simon Zoller created a nervy moment in the Arsenal penalty area when he managed to squeeze between Per Mertesacker and Rob Holding, though the pair were eventually able to recover.

The offside flag spared the Gunners' blushes when Konstantin Rausch whipped a dangerous ball into the box for Zoller, with Ospina fortunate not to give away a penalty for a foul on Jonas Hector—which required the German to be withdrawn minutes later—after the ball spilled to him.

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At the other end, Theo Walcott latched onto Alex Iwobi's pass on the right, but under pressure from Rausch, he scuffed well wide of the target, while Olivier Giroud should have done better when he rose to meet a Sanchez cross.

What's more, the hosts' play was static and lacked initiative. Bleacher Report's James McNicholas remarked on Arsenal's struggles in the centre, while ESPN FC's Mattias Karen noted their failure to adapt to a 3-4-3 formation:

Kolasinac's introduction at the break put an end to the system, and the Bosnian made an instant impact when he lashed home a volley from Walcott's deflected cross.

The goal injected some drive into Arsenal, and Ainsley Maitland-Niles came close to putting them in front when he made a darting run through Koln's defence into the box, but the youngster failed to round Timo Horn.

Sanchez was the man to make the difference as ever. After picking the ball up wide on the left, the Chilean cut inside before curling home a sumptuous effort from the edge of the area.

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Cordoba forced a save from Ospina as Koln showed a flicker of life, but the Gunners were able to exert far more control over the contest as the second half wore on. Bellerin added a third when he finished Walcott's rebound from close range with under 10 minutes remaining.

While the hosts won comfortably in the end and Koln are their strongest opponents in Group H, the first half offered a timely warning they cannot afford to take the Europa League lightly if they intend to win it. Arsenal's next Europa match is against BATE in Belarus on September 28.