CELTIC boss Ange Postecoglou insists his men did themselves proud by giving Bayer Leverkusen a game in their own backyard.

Postecoglou's men suffered heartache in the Bay Arena after losing 3-2 on the night.

It was a result that shunted Celtic out of the Europa League and into the last 32 of the Europa Conference League.

The Aussie believes that his men gave the hosts such a fright and came within an ace of winning a European match for the first time ever on German soil.

The 56-year-old admits that if Celtic continue to play in the same manner they will reduce the gap between themselves and top tier European sides.

Postecoglou said: "It is a tough one to take as we kind of hung in there and gave ourselves a chance to pull off a great result. Ultimately they are a good team and we just didn't sort of finish the game off in the way that we could have.

"Credit to the players as Leverkusen are a fantastic team and we came to their backyard and we gave them a game. There is still a gap between us and them and that's what we need to bridge. In all our European games we have taken it to some very good opponents.

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"We know there is a gap between us and the best and we will bridge that gap if we keep taking this approach whenever we play these teams.

"They knocked us 4-0 at home and we gave them a fright here and hopefully next time that gap is even smaller.

"We just hung in there and we weren't able to control the game the way we wanted to because they have quality in their side and they are always a threat on the counter-attack. We had to be a bit wary about that.

"Joe (Hart) made some good saves and the back four did well to keep us in the game but we just couldn't hang on in the end.

"I was disappointed for the players as they put in a massive effort. The Celtic supporters were unbelievable and they were brilliant.

"I am hoping in their disappointment tonight at least they walk away knowing that the guys in the green and white hoops gave everything for them and they gave them something to cheer about ."