Match ends, Sparta Prague 4, Celtic 1.
Celtic are out of the Europa League with two games to spare after a second successive 4-1 defeat by Sparta Prague heaped more pressure on Neil Lennon.
Odsonne Edouard marked his return to the XI with a stylish opener, but David Hancko exposed poor defending to level.
Lukas Julis added two to his hat-trick in Sparta's Glasgow win and substitute Srdan Plavsic added a late fourth.
Celtic have now taken one point from their four group games after a fourth loss in nine games in all competitions.
Lennon's side - who have won just twice in those nine matches - can now only reach a tally of seven points; a mark which is guaranteed to be beaten by at least two of Lille, AC Milan or Sparta.
Trailing Rangers by 11 points in the Scottish Premiership - albeit with two games in hand - Celtic needed to get back to winning ways to get into some sort of contention in Group H.
The early omens were not good as David Moberg Karlsson flashed wide with a long-range shot that looked like it had the beating of goalkeeper Scott Bain.
Things started looking up for Celtic when Edouard received Callum McGregor's pass, slalomed one way then the other as he advanced towards goal then converted past Florin Nita.
But the Czech side soon levelled from a corner. Scott Brown did not clear his lines, allowing David Pavelka to get away a mis-hit shot, and Hancko buried the ball as he and two others were being played onside by McGregor.
And the Prague side moved into the lead when Borek Dockal's low cross from the right eliminated all four Celtic defenders and Julis forced in at the back post, though the striker did appear to be offside.
Sparta could, and probably should, have added to their lead when Dockal's free-kick was headed on to a post by Ladislav Krejci just before the interval.
An Edouard free-kick early in the second period was touched wide by Nita and Ryan Christie then curled an effort wide for Celtic.
Edouard should have levelled when found by Olivier Ntcham but his tame shot was collected by the keeper.
Tom Rogic, so often a scorer of vital Celtic goals, was sent on in place of Brown for the final 24 minutes but the Australian could not spark a revival, with Julis soon putting the game to bed.
Hatem Elhamed's defensive header was poor and he then missed an interception as Karlsson sped away on the left to cross for Julis to volley past Bain.
And Celtic were found wanting at the back again as Plavsic raced on to another Dockal pass, rounded Bain and finished past McGregor on the goal line.
Man of the match - Lukas Julis
What did we learn?
Celtic restored Elhamed and Christopher Jullien to the right side of their much maligned defence to compliment Kristoffer Ajer and Diego Laxalt.
And the new back four struggled from open play and at set pieces, Sparta taking advantage as they had done when they won 4-1 in Glasgow.
In James Forrest's continued absence, the Celtic attack lacks pace and a goal threat from the right.
Positively for the Scottish champions, Edouard looked much more like the striker that started the season with a hat-trick against Hamilton back in August.
- Since it was rebranded in 2009-10, Celtic have won just two of their 24 away games in the Europa League (D11 L11).
- Celtic are yet to win in the Europa League this season (D1 L3), with their winless run in the competition (excluding qualifiers) standing at seven matches (D2 L5).
- Julis has scored five goals in his last two Europa League games - two more than he netted in his first 19 matches in the competition.
- Edouard has been directly involved in six goals in his last eight Europa League games (four goals, two assists).
- The Frenchman has scored in two of his past three away Europa League appearances.
Celtic begin their defence of the Scottish League Cup at home to Ross County on Sunday (14:00 GMT) and take on Milan in Italy in the penultimate round of Europa League group fixtures next Thursday (17:55).
- 33HanckoSubstituted forSoucekat 67'minutesBooked at 89mins
- 32Aalen VindheimBooked at 29mins
- 25TravnikSubstituted forKrejciat 76'minutes
- 37KrejciBooked at 57mins
- 39JulisSubstituted forYankov Minchevat 86'minutes
- 7Moberg KarlssonSubstituted forPlavsicat 86'minutes
- 11Yankov Minchev
- 8BrownSubstituted forRogicat 66'minutes
- 22EdouardSubstituted forKlimalaat 82'minutes
- Tobias Stieler
- Shots on Target
Second Half ends, Sparta Prague 4, Celtic 1.
Goal! Sparta Prague 4, Celtic 1. Srdan Plavsic (Sparta Prague) left footed shot from the centre of the box to the bottom left corner. Assisted by Borek Dockal following a fast break.
Hatem Elhamed (Celtic) wins a free kick on the right wing.
Foul by Ladislav Krejci I (Sparta Prague).
Foul by Ladislav Krejci II (Sparta Prague).
Ryan Christie (Celtic) wins a free kick in the defensive half.
Filip Soucek (Sparta Prague) is shown the yellow card for a bad foul.
Foul by Filip Soucek (Sparta Prague).
Olivier Ntcham (Celtic) wins a free kick in the defensive half.
Foul by Martin Yankov Minchev (Sparta Prague).
Hatem Elhamed (Celtic) wins a free kick in the defensive half.
Foul by Diego Laxalt (Celtic).
Andreas Aalen Vindheim (Sparta Prague) wins a free kick on the right wing.
Substitution, Sparta Prague. Srdan Plavsic replaces David Moberg Karlsson.
Substitution, Sparta Prague. Martin Yankov Minchev replaces Lukas Julis.
Foul by Diego Laxalt (Celtic).
Borek Dockal (Sparta Prague) wins a free kick in the defensive half.
Substitution, Celtic. Patryk Klimala replaces Odsonne Edouard.
Corner, Sparta Prague. Conceded by Olivier Ntcham.
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