Celtic followed their League Cup triumph with a shock Scottish Premiership slip-up as they were held by Covid-weakened St Mirren in Paisley.
The visitors, who won the first trophy of the Ange Postecoglou era on Sunday, could not find a way past inspired stand-in goalkeeper Dean Lyness.
The surprise draw ends Celtic’s six-game league winning run and leaves them six points behind leaders Rangers.
St Mirren, in ninth, are four points clear of bottom club St Johnstone.
The hosts started with three teenagers in a game they twice tried to have called off after 11 players tested positive, but emerged with a remarkable point despite Celtic’s 31 shots and 83% possession.
Celtic can point to personnel problems of their own, with an injury list stretching into double figures and cup final match-winner Kyogo Furuhashi a notable absentee.
But the stalemate – in their last game before crowds are temporarily capped at 500 – is a huge blow to Celtic’s title hopes as the rearranged winter break beckons.
St Mirren manager Jim Goodwin hailed “the best point this club have had for a long time” and revealed some of his young players hadn’t even met their senior colleagues before the game.
“It was an incredible performance from the team – they gave everything for the jersey,” said Goodwin.
“Sometimes managers get credit, but I can’t take a great deal of credit for that. They came out fighting when it seemed the whole world was against us. The kids deserve a special mention.”
Kyogo’s movement and finishing prowess were sorely lacking for the visitors as they failed to turn a barrage of pressure into a breakthrough.
Lyness – on just his third start in two-and-a-half years with St Mirren – impressively tipped a first-half Nir Bitton free-kick wide and denied Mikey Johnston a solo goal after the winger jinked past three players.
Johnston had a close-range effort cleared off the line by Joe Shaughnessy after the break, while Liel Abada and Callum McGregor also found Lyness an unpassable barrier and Josip Juranovic shaved a post with a free-kick.
But Celtic ran out of ideas and were repelled by a heroic defensive effort from Goodwin’s side, whose youthful bench did not have a first-team appearance between them.
The home team gave Celtic a couple of scares too. Shaughnessy had a close-range header deflected just wide and Curtis Main forced a save from Scott Bain, who was deputising for Joe Hart.
Those were rare moments of respite but the Paisley men continually put their bodies on the line amid a succession of shots and crosses to claim a memorable point.
Man of the match – Dean Lyness
What did we learn?
St Mirren are now 10 games without a win – but their fans rightly celebrated a massive result.
The Paisley club were reluctant participants, with Goodwin saying the SPFL “bent the loan rules” so six under-18 players could be recalled from Lowland League clubs to fill out the squad.
He had little option but to put trust in untried youth and was rewarded with a performance full of energy, passion, and commitment.
Captain Shaughnessy shone at the heart of a defence under huge pressure, while teenagers Dylan Reid, Jay Henderson and debutant Kieran Offord can be proud of their showings.
Celtic escaped with a last-gasp winner in their previous Premiership outing at Ross County, but were unable to repeat the trick.
Nineteen-year-old striker Owen Moffat, making his first start, proved an ineffectual deputy for Kyogo and Celtic struggled to penetrate St Mirren’s low defensive block.
With David Turnbull joining Jota and James Forrest on the sidelines, Postecoglou’s squad lacks the depth to cope without so many key attacking players.
What did they say?
Celtic manager Ange Postecoglou: “It’s a game we should have won and we created enough opportunities to do that, we dominated.
“We just lacked a little bit of composure and quality in the front third. The expectations of this club are that you go in every game to win and the payers are disappointed – as they should be. “
Both sides finish up before the winter break with games on Sunday in front of 500 fans. St Mirren face leaders Rangers at Ibrox (15:00 GMT), with Celtic away to bottom club St Johnstone (15:00).
Player of the match
Squad number42Player nameMcManus
Squad number26Player nameLyness
Squad number12Player nameHenderson
Squad number4Player nameShaughnessy
Squad number22Player nameFraser
Squad number3Player nameTanser
Squad number18Player nameDunne
Squad number15Player nameReid
Squad number11Player nameKiltie
Squad number33Player nameOfford
Squad number10Player nameMain
Squad number44Player nameMillar
Squad number56Player nameRalston
Squad number29Player nameBain
Squad number42Player nameMcGregor
Squad number20Player nameCarter-Vickers
Squad number5Player nameScales
Squad number6Player nameBitton
Squad number18Player nameRogic
Squad number73Player nameMoffat
Squad number57Player nameWelsh
Squad number11Player nameAbada
Squad number88Player nameJuranovic
Squad number19Player nameJohnston
Squad number30Player nameShaw
Squad number3Player nameTaylor
- 3TanserBooked at 18mins
- 33OffordBooked at 39minsSubstituted forMcManusat 88′minutes
- 57WelshBooked at 33mins
- 5ScalesSubstituted forTaylorat 89′minutes
- 6BittonSubstituted forShawat 81′minutes
- 73MoffatSubstituted forJuranovicat 61′minutes
- 18RogicBooked at 64mins
Match ends, St. Mirren 0, Celtic 0.
Second Half ends, St. Mirren 0, Celtic 0.
Hand ball by Michael Johnston (Celtic).
Attempt missed. Michael Johnston (Celtic) right footed shot from the centre of the box is too high. Assisted by Liam Shaw following a corner.
Corner, Celtic. Conceded by Matthew Millar.
Corner, Celtic. Conceded by Daniel McManus.
Foul by Greg Taylor (Celtic).
Jay Henderson (St. Mirren) wins a free kick on the right wing.
Foul by Liam Shaw (Celtic).
Greg Kiltie (St. Mirren) wins a free kick in the defensive half.
Corner, Celtic. Conceded by Jay Henderson.
Attempt missed. Josip Juranovic (Celtic) right footed shot from the right side of the box misses to the left. Assisted by Anthony Ralston.
Substitution, Celtic. Greg Taylor replaces Liam Scales.
Attempt saved. Anthony Ralston (Celtic) header from the centre of the box is saved in the top right corner. Assisted by Josip Juranovic with a cross.
Substitution, St. Mirren. Daniel McManus replaces Kieran Offord because of an injury.
Corner, Celtic. Conceded by Matthew Millar.
Attempt blocked. Liam Scales (Celtic) header from the centre of the box is blocked. Assisted by Josip Juranovic with a cross.
Substitution, Celtic. Liam Shaw replaces Nir Bitton.
Foul by Cameron Carter-Vickers (Celtic).
Curtis Main (St. Mirren) wins a free kick in the defensive half.