Ange Postecoglou has opened up on his first experience of Champions League football with Celtic.
The Australian enjoyed two successful seasons in Glasgow, winning five out of six trophies, before joining Tottenham Hotspur in June.
And he detailed the obstacles he came up against while in charge of the Parkhead side in Europe's top competition.
Speaking to GOAL, he said: "Champions League football is just unrelenting, it's fantastic, it's confronting.
"It challenges you in every way. Sometimes you're going in to the most hostile of environments, facing the best footballers on the planet with zero hope of achieving anything but believing that you can.
"It's also very addictive. You want to go back and do it again and again. It is the pinnacle of club football."
Meanwhile, Matt O'Riley has expressed his delight for Celtic team-mate Oh Hyeon-gyu after the South Korean's double against Hibernian.
The striker has found his game time limited this season, with the match against Nick Montgomery's side marking only his second start of the season.
And O'Riley feels Oh will go from strength to strength. Speaking to Celtic TV, he said: "He has had to wait for his chance, at times, and it’s not easy when you are only getting 15-20 minutes to get a goal.
“I think he deserves it. He works really hard every day, so I am very happy for him.”
