For the first time since 1958, Celtic have lost four home games in a row. Out of the Europa League, 11 points behind Rangers in the Scottish Premiership title race, and now out of the League Cup.
Sunday's 2-0 home loss to Ross County led to fans gathering outside Celtic Park demanding Neil Lennon's removal as manager.
What has gone wrong at a club that have won nine consecutive league titles and will claim a fourth consecutive treble should they beat Hearts on 20 December in the Scottish Cup final?
And, crucially, can Lennon survive this crisis to remain as manager?
- Lennon admits Celtic pressure mounting
- Ross County stun Celtic in League Cup
- Angry fans gather at Celtic Park
- What now for Lennon & Celtic?
How has the pressure built?
In August, Celtic suffered their earliest Champions League exit in 15 years after falling to a shock defeat at the hands of Hungary's Ferencvaros in Glasgow.
Then, defender Boli Bolingoli was found to have broken strict Covid-19 protocols, earning the wrath of the club and leading to Celtic having two games postponed.
Amid that, though, Lennon's side won eight of their first nine league games as they chased the fabled 10 league titles in a row. But then their problems really began.
They lost meekly 2-0 at home to Rangers, 3-1 against AC Milan in the Europa League and dropped more points in a 3-3 draw at Aberdeen. And, although they drew with Lille in France and beat Aberdeen 2-0 in the Scottish Cup semi-final, they have since been thrashed 4-1 home and away by Sparta Prague.
In summary, it is just two wins in their last 10 games.
What is Lennon saying?
Surely a home tie against a Ross County side who had never won at Celtic Park and hadn't beaten a top-flight team in seven attempts would enable them to steady the ship? Apparently not.
Goals from Ross Stewart and Alex Iacovitti knocked Celtic out of the League Cup and inflicted their first domestic cup loss in 36 games, a record stretching back to a penalty shoot-out loss to Rangers in 2016.
Afterwards, Lennon conceded his previous record in two spells - winning five titles, three Scottish Cups and a League Cup - "doesn't count for anything at the minute".
"If you keep losing games, there is an expectation at this club, there's a demand for excellence and there's a demand for wins - I am fully aware of that," he said.
"I am not standing here like the happy clapper saying everything's okay, because it's not. But we'll do everything we can, if I've still got the opportunity to do that, to turn things around.
"Today's result wouldn't have helped, put it that way."
Is it the fault of the players?
Speaking on Sportsound, former Scotland striker Billy Dodds pointed the finger at five Celtic players in particular, saying he thinks they have "chucked it".
"This was their chance to step up, show all these rumours [that Lennon had lost the dressing room] were not true. Show they were with the manager, that they are still good players, that they can challenge Rangers. But I saw none of that.
"I thought the Celtic performance defensively was horrific and, going forward, I honestly thought a lot of the players had chucked it. Albian Ajeti, Odsonne Edouard, Tom Rogic, Hatem Abd Elhamed... there was just nothing. Kristoffer Ajer, too. I don't think he's as good as he thinks he is.
"Neil Lennon has done a lot for the club. When he needed these players today - they let him down."
Former Celtic goalkeeper Pat Bonner concurred, saying "the players are not responding to him" and questioned their attitude. "They've gone so far back it's incredible," he added.
What's next for Celtic?
Whether Lennon remains in his post or not will be known in the coming days, but the games are still coming thick and fast.
On Thursday, Celtic travel to face an in-form AC Milan side who are leading Italy's Serie A. Then, in the Premiership, four of their next five games are at home.
The Scottish Cup final with Hearts is three weeks away, with a potentially defining trip to Ibrox to take on leaders Rangers 12 days later.
Lennon said on Friday he had the "full support" of chief executive Peter Lawwell and major shareholder Dermot Desmond. The next few days will demonstrate if that it still the case.
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