Match ends, Legia Warsaw 4, Celtic 1.
Ronny Deila suffered a nightmare first loss as Celtic boss with a heavy defeat by Legia Warsaw in the Champions League third qualifying round first leg.
Celtic had taken an early lead in Poland with a curling shot into the top corner from Callum McGregor.
However, Miroslav Radovic scored twice, and it got worse before half-time when Efe Ambrose was sent off.
Ivica Vrdoljak twice missed from the penalty spot, but Michal Zyro and Jakub Kosecki both found the net late on.
If it was not for some heroic goalkeeping by Fraser Forster, this could have been a real embarrassment.
As it is, their hopes of progress are still alive, although they need to win at least 3-0, but the away goal and the balanced nature of the match in the first half will give Deila belief his side can turn the tie round.
However, the disjointed nature of Celtic's performance and their lack of ability to close the game down after being reduced to 10 men must be a concern.
There was no sign of the chaotic manner in which the game would unfold when McGregor added to his burgeoning reputation as he opened the scoring, just as he had in Iceland in the previous round.
The goal had a similar feel about it too as he cut in from the right before beating the goalkeeper at his near post, this time with a curling shot beyond the fingertips of the diving Dusan Kuciak.
But Celtic let the lead slip almost as soon as they had created it.
Radovic was allowed space inside the box and his well-hit effort was too powerful for Forster to keep out.
The game was extremely open, with neither defence looking entirely comfortable and more goals seemed a certainty.
And though Kris Commons and Teemu Pukki went close for Celtic it was the home side who took the lead.
Again Celtic's back-line - and Ambrose in particular - looked vulnerable and when Ondrej Duda headed across goal, Radovic was unmarked and gleefully slid in to beat Forster from close range.
McGregor forced a decent save from Kuciak but there was further bad news for Celtic to contend with before the interval.
As Michal Kucharczyk bore down on goal, Ambrose attempted to get a toe to the ball only to bring down the Legia man, leaving the referee a straightforward decision to brandish the red card.
Ambrose's departure meant Charlie Mulgrew dropped back to defence and it was the captain's careless challenge on Lukasz Broz that led to Legia being awarded a penalty.
But as the few Celtic fans in the stadium began to sense their Champions League dreams fading, they were granted a brief reprieve as Vrdoljak sent the spot-kick wide.
Legia pressed hard for the goals they hoped would put the tie beyond Celtic and Zyro rounded off an impressive performance with a headed goal following great work by the excellent Radovic.
Forster then saved a Vrdoljak penalty but in injury time substitute Kosecki added a fourth, to leave Celtic needing a monumental performance at Murrayfield next Wednesday if they are to avoid a place in the Europa League play-offs.
- 15AstizBooked at 22mins
- 33ZyroSubstituted forSaganowskiat 87'minutes
- 18KucharczykSubstituted forKoseckiat 75'minutesBooked at 89mins
- 2Júnior Dossa Momade
- 5van Dijk
- 4AmbroseBooked at 44mins
- 21MulgrewBooked at 86mins
- 15CommonsSubstituted forGriffithsat 75'minutesBooked at 89mins
- 16BergetSubstituted forIzaguirreat 62'minutes
- 20PukkiSubstituted forKayalat 45'minutesBooked at 88mins
- Pol van Boekel
- Shots on Target
Second Half ends, Legia Warsaw 4, Celtic 1.
Goal! Legia Warsaw 4, Celtic 1. Jakub Kosecki (Legia Warsaw) left footed shot from the centre of the box to the bottom right corner. Assisted by Lukasz Broz.
Attempt saved. Marek Saganowski (Legia Warsaw) left footed shot from the right side of the six yard box is saved in the centre of the goal. Assisted by Tomasz Brzyski.
Jakub Kosecki (Legia Warsaw) is shown the yellow card.
Leigh Griffiths (Celtic) is shown the yellow card.
Beram Kayal (Celtic) is shown the yellow card for a bad foul.
Tomasz Brzyski (Legia Warsaw) wins a free kick in the attacking half.
Foul by Beram Kayal (Celtic).
Substitution, Legia Warsaw. Marek Saganowski replaces Michal Zyro.
Penalty saved! Ivica Vrdoljak (Legia Warsaw) fails to capitalise on this great opportunity, right footed shot saved in the bottom right corner.
Charlie Mulgrew (Celtic) is shown the yellow card for a bad foul.
Penalty Legia Warsaw. Jakub Kosecki draws a foul in the penalty area.
Penalty conceded by Charlie Mulgrew (Celtic) after a foul in the penalty area.
Goal! Legia Warsaw 3, Celtic 1. Michal Zyro (Legia Warsaw) header from the centre of the box to the bottom left corner. Assisted by Miroslav Radovic with a cross following a corner.
Corner, Legia Warsaw. Conceded by Virgil van Dijk.
Attempt blocked. Michal Zyro (Legia Warsaw) left footed shot from the centre of the box is blocked. Assisted by Miroslav Radovic.
Ondrej Duda (Legia Warsaw) wins a free kick in the attacking half.
Foul by Stefan Johansen (Celtic).
Ivica Vrdoljak (Legia Warsaw) wins a free kick in the defensive half.