Match ends, Celtic 1, St. Johnstone 1.
The pressure on manager Neil Lennon intensified further as his faltering Celtic fell 13 points behind Premiership leaders Rangers with a draw against St Johnstone in Glasgow.
The visitors went ahead when Chris Kane slid home Stevie May's cross but Mohamed Elyounoussi's header restored parity with seven minutes remaining.
It now means Lennon's men, who have two games in hand, have won just two of their past 12 games and are also winless at home since the middle of September.
Fans protested outside Celtic Park last weekend following defeat by Ross County in the League Cup, triggering club chief executive Peter Lawwell to back his manager in a statement on Tuesday.
However, this stalemate means his side have now dropped nine points in five league games.
Callum Davidson's Saints, now undefeated in 11 matches over 90 minutes, move level on points with seventh-place Kilmarnock.
- Reaction & as it happened
- 'Can I turn it around? Of course I can' - Lennon defiant as Celtic fail to win again
- Rangers thrash Ross County
It was a day of big numbers for Celtic as captain Scott Brown made his 600th appearance for the club, McGregor his 300th and Lennon himself marked 20 years since he first joined Celtic as a player.
But the stat that mattered most to the home side was whether they could register a win.
They set about doing that with Odsonne Edouard playing a one-two with Tom Rogic and getting away a shot that took a nick off a Saints defender before goalkeeper Zander Clark gathered.
Rogic should have hit the target with a header after Christopher Jullien nodded Ryan Christie's free-kick back into a busy area.
Edouard did find his mark with a shot off McGregor's through ball but Clark was well positioned to save and McGregor's rebound effort was wayward.
St Johnstone, having travelled to Glasgow unbeaten in five league games, posed the hosts problems through a volley from May that was headed away by Nir Bitton near the goal line and another effort from the striker that fizzed across the face of goal.
Bitton tried to usher the ball over the line at a corner in the second half but Clark was alert again and the Perth side were soon in front.
Kane had replaced the injured Michael O'Halloran in the first half and he was left free to convert May's dangerous cross after Celtic failed to clear their lines at a free-kick.
Edouard forced another save from Clark as the hosts toiled but moments later Christie's cross was headed backwards by Elyounoussi and Celtic had a quick equaliser.
Further efforts came in from Turnbull, Christie and Elyonoussi as the home side chased victory but St Johnstone held out.
Man of the match - Zander Clark
What did we learn?
Celtic have flitted between three and four at the back this season and Lennon re-established a 3-5-2 for the visit of Saints.
Defensively, the home side did not give up as many chances as they had in recent matches but the expected width did not materialise, once again emphasising the gap left by the absent James Forrest.
Distribution was poor and creativity lacking from Celtic, which only encouraged a well-drilled St Johnstone side.
For their part, Saints were not just organised, they carried a threat even before their opener and were good value for a point.
What did they say?
Celtic manager Neil Lennon: "I'm really disappointed with the result and aspects of the performance. We dominated the game possession-wise again but we looked tentative. I understand that to a certain degree but they need to rise above that.
"For me we're not working the goalkeeper anywhere near enough. There's a lack of speed in our play, lack of movement. And we can't keep a clean sheet."
St Johnstone manager Callum Davidson: "The players were tremendous. They worked unbelievably hard off a good shape. We had a wee bit of sustained pressure when we got the goal.
"Could we hang on for the victory? Unfortunately we didn't but I'm really proud of my players. I'll take the draw. It's what we deserve with our efforts and application."
Celtic complete their Europa League campaign at home to Lille on Thursday evening and host Kilmarnock in the Premiership next Sunday. St Johnstone are at home to Livingston in the league on Saturday.
- 35AjerSubstituted forElyounoussiat 81'minutes
- 8BrownSubstituted forGriffithsat 59'minutes
- 42McGregorBooked at 78mins
- 93LaxaltSubstituted forTaylorat 45'minutes
- 18RogicSubstituted forTurnbullat 68'minutes
- 15McNamaraBooked at 90mins
- 13BrysonBooked at 54minsSubstituted forCraigat 86'minutesBooked at 90mins
- 11O'HalloranSubstituted forKaneat 26'minutesBooked at 68mins
- 10WotherspoonBooked at 64mins
- David Munro
- Shots on Target
Second Half ends, Celtic 1, St. Johnstone 1.
Foul by Christopher Jullien (Celtic).
Jamie McCart (St. Johnstone) wins a free kick in the defensive half.
Dan McNamara (St. Johnstone) is shown the yellow card for a bad foul.
Liam Craig (St. Johnstone) is shown the yellow card for a bad foul.
Mohamed Elyounoussi (Celtic) wins a free kick in the attacking half.
Foul by Liam Craig (St. Johnstone).
Foul by Ryan Christie (Celtic).
Stevie May (St. Johnstone) wins a free kick on the left wing.
Attempt missed. Mohamed Elyounoussi (Celtic) header from the centre of the box misses to the right. Assisted by Leigh Griffiths with a cross following a corner.
Corner, Celtic. Conceded by Dan McNamara.
Attempt saved. Ryan Christie (Celtic) left footed shot from the right side of the box is saved in the bottom left corner.
Substitution, St. Johnstone. Liam Craig replaces Craig Bryson.
Attempt missed. David Turnbull (Celtic) header from the centre of the box is high and wide to the left. Assisted by Mohamed Elyounoussi with a cross.
Goal! Celtic 1, St. Johnstone 1. Mohamed Elyounoussi (Celtic) header from the centre of the box to the top left corner. Assisted by Ryan Christie with a cross.
Substitution, Celtic. Mohamed Elyounoussi replaces Kristoffer Ajer.
Corner, Celtic. Conceded by Zander Clark.
Attempt saved. Odsonne Edouard (Celtic) left footed shot from outside the box is saved in the centre of the goal. Assisted by Leigh Griffiths.
Goal! Celtic 0, St. Johnstone 1. Christopher Kane (St. Johnstone) right footed shot from very close range to the bottom right corner. Assisted by Stevie May.
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