Ange Postecoglou's Celtic side has had a tough start to its Champions League campaign, losing 3-0 to European giants Real Madrid at home in Glasgow.
Postecoglou was left to lament missed chances, after Real Madrid gave Celtic a lesson in cool finishing in the first game of Group F.
But while the result was disappointing, the club still celebrated its return to Champions League football after a five-year absence in front of a packed house at Celtic Park.
The atmosphere was electric before the match, with Celtic fans producing a display of a giant leprechaun with the sign "Back with a bang".
Celtic came into the game on a high after a 4-0 weekend hammering of cross-town rivals Rangers in the Old Firm derby.
Postecoglou had maintained his side would keep its attacking mindset, even against the 14-times winner of Europe's top club competition.
And the home side kept the big crowd entertained, putting the pressure on the visitors from the opening minute, as Liel Abada had a shot turned wide by Eder Militao.
More chances came, with Abada hitting straight at keeper Thibaut Courtois when put in on goal, and in the 20th minute Callum McGregor hit the post with a fierce shot.
Real began to find their way, with the likes of Dani Carvajal and Federico Valverde causing Celtic problems down the right.
There was bad news for the visitors on the half-hour, as star striker Karim Benzema limped off with a knee injury.
Real had chances of their own, and right before half-time Celtic 'keeper Joe Hart had to pull off a strong save to deny Vinicius Jr.
It was goal-less at the break, but Real was clinical despite the injury to Benzema and killed the game by scoring three goals in their only three shots on target in the second half.
First it was Vinicius Jr who thumped home a close-range finish from a Valverde cross in the 56th minute.
Four minutes later, Luka Modric extended the lead with a shot from inside the box and substitute Eden Hazard wrapped up the points in the 77th minute with a simple close finish from a fine assist by Dani Carvajal.
After the game, Postecoglou acknowledged the visitors' display and the fine margins in the Champions League.
"You know at this level you're not going to dominate the whole game, you get a certain amount of opportunities to punish the opposition.
"Unless you experience it, it's probably the hardest way to learn but the best way to learn.
"This is a special football club … the responsibility lies on me to get this football club to the level it deserves to be."
In the other game in the group, Ukraine side Shakhtar Donetsk scored an impressive 4-1 away win over RB Leipzig, including a double by forward Marian Shved to gain the early advantage in the fight for qualification from group F.
In other groups, Red Bull Salzburg drew 1-1 with AC Milan, Manchester City had a 4-0 away win over Sevilla, Portuguese side Benfica downed Maccabi Haifa 2-0, PSG defeated Juventus 2-1 in Paris, Dinamo Zagreb beat Chelsea 1-0 and Borussia Dortmund beat FC Copenhagen 3-0.
Reuters/ABC
