Hector Bellerin is confident Arsenal can go far in the Europa League after winning a tense opening group game.
Amid crowd trouble largely involving away fans infiltrating the home sections of the Emirates Stadium, the kick-off was delayed by an hour.
Cologne scored a stunning opener, with David Ospina caught off his line and beaten from 40 yards, but the Gunners came from behind through Sead Kolasinac, Alexis Sanchez and Bellerin in the second half.
“It’s a new competition for us so we had to set the tone," Bellerin told BT Sport.
"We think we are one of the best teams in the competition so we have to show that on the pitch.
“I’m very happy for the victory. We were ready to play at eight o’clock, but these things happen. We started a bit with cold feet but after that it just worked.
“The win in the league against Bournemouth and today’s win, coming back from behind, gives you a boost. We will train over the next two days and then be ready for Chelsea."
