With three rounds to go in the inaugural Champions League league phase, Real Madrid, Manchester City, Juventus and Paris Saint-Germain are in genuine jeopardy.
To achieve automatic qualification into the round of 16, teams must finish in the top eight.
Those in ninth to 24th enter a round of two-legged play-offs in February, with the winners taking the other eight spots.
Teams that finish anywhere from 25th to 36th will be eliminated from this season's competition, with no access to the Europa League.
As it stands, four heavyweights of European football are in danger. Paris Saint-Germain are facing full elimination, with holders Real Madrid just above the drop zone in 24th place.
Manchester City are also struggling. Pep Guardiola's side are only 17th, far away from a coveted top-eight spot.
So too are 19th-placed Juventus, who will face off against City on Tuesday in what could be a decisive fixture in the race for qualification.
A big gun, it seems increasingly likely, will fall.
What are the dates for the final three league phase matches?
Matchday six - December 10-11
Matchday seven - January 21-22 2025
Matchday eight - January 29 2025
Champions League league phase table in full
This week's crucial Champions League fixtures
December 10: Atalanta vs Real Madrid, 8pm kick-off
December 10: RB Salzburg vs PSG, 8pm kick-off
December 11: Juventus vs Man City, 8pm kick-off
Atalanta trip arrives at the wrong time for Madrid
The holders of Europe's elite trophy have undoubtedly been the shock of the competition so far. Defeats to AC Milan, Lille and most recently Liverpool have marked miserable outings in the Champions League and a trip to the Gewiss Stadium to face Atalanta likely arrives at the wrong time.
Gian Piero Gasperini's side remain unbeaten with three league phase games to go, after making light work of Young Boys, Stuttgart and Shakhtar Donetsk, while also drawing to Celtic and Arsenal.
Real Madrid's Kylian Mbappe missed two one-on-ones and had three goals disallowed for offside in his Clasico debut
Image: Real Madrid's Kylian Mbappe scored his first goal for the club against Atalanta in the UEFA Super Cup
However, Madrid can take confidence from the fact they have already beaten their upcoming opponents this season, following their 2-0 win in the UEFA Super Cup back in August - a game that saw Kylian Mbappe score his first goal for Los Blancos.
More frustration on the way for Man City?
Two big names continue to flounder in the lower levels of the table: Man City and Juventus.
They sit level on points - with Guardiola's City side only ahead due to their superior goal difference - heading into Tuesday's clash but more frustration could be on the cards for the 2022/23 champions here.
Man City stopped the rot with a routine victory against Nottingham Forest last week but stumbled in their next outing against Crystal Palace, where two more points were dropped following the 2-2 draw away from home.
Phil Foden reacts after wasting a chance to score at Anfield
Image: Manchester City are in danger of dropping out of the Champions League with Pep Guardiola's side in 17th
Juventus are a team rebuilding under Thiago Motta, with several young and exciting players at their disposal, but have shown their resilience in the competition so far.
Goals have been hard to come by but their defensive performances have been stoic, with only Arsenal, Liverpool, Aston Villa, Atalanta and Inter Milan conceding less than their tally of five so far.
An ominous statistic that will likely linger in the minds of City, who are in desperate need of a win for both their chances of qualification and confidence.
Must-win game for PSG
It has been downhill for PSG since they kickstarted the European campaign with a 1-0 win against Girona, but they have endured one of the toughest fixture lists in the Champions League up until now.
Losses to Arsenal, Atletico Madrid and Bayern Munich have followed, as well as dropping points to PSV, which has seen them slip into 25th.
Image: One of PSG's three defeats in the Champions League arrived against Arsenal
Therefore the clash against RB Salzburg, who are one of the few teams below them in 34th, now becomes a must-win game for the Ligue 1 champions.
Next up after that? Fellow strugglers Man City. The survival of last season's semi-finalists now hinges on their next two performances.
When are the 2024/25 Champions League knockout stages?
Knockout round play-offs: February 11/12 and February 18/19, 2025
Round of 16: March 4/5 and March 11/12, 2025
Quarter-finals: April 8/9 and April 15/16, 2025
Semi-finals: April 29/30 and May 6/7, 2025
Final: May 31, 2025
When and where is the 2025 Champions League final?
The 2024/25 UEFA Champions League season will take place in Munich at the Allianz Arena on May 31, 2025.