Real Madrid's three-year reign as Champions League holders is over after a shock loss to Ajax and that result has cast increasing doubt over the future of coach Santiago Solari.
The Spanish giants are no stranger to a swift managerial switch and there are plenty of candidates currently available should Solari get sacked - be it now or at the end of the season.
Here are just some of the coaches Real Madrid could be considering...
#1 Jose Mourinho
While he left the Santiago Bernabeu in typically dramatic fashion, Jose Mourinho has seemingly been on the Madrid charm offensive in recent weeks.
Following his departure from Manchester United, the manager hasn't gone into hiding, instead embracing a number of media roles.
"Working at Real Madrid is a unique experience and different to the rest of the clubs I have been at," Mourinho told Deportes Cuatro in March.
"We did fantastic things and we won the league in a unique way. We also had bad moments, I made mistakes, but the experience made me a better manager and person.
Though Mourinho may have left the Bernabeu on bad terms and fell short of silverware a number of times, his win ratio of 71.9 per cent with Madrid is the best of any club he's managed and a big tick next to his name as far as Real will be concerned.
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#2 Massimiliano Allegri
That admission would surely have caught Madrid's attention, who could make another offer to Massimiliano Allegri after he respectfully rejected the chance to succeed Zinedine Zidane last summer.
Since taking charge of Juve in 2014, he's claimed 10 trophies and won the Serie A title every season. However, the consensus is that this season is likely to be his last with the Bianconeri - especially if they are eliminated by Atletico Madrid in the Champions League last 16.
While regularly falling short in the Champions League, Madrid and Allegri may feel a union is exactly what they both need to succeed on Europe's biggest stage moving forward.
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#3 Mauricio Pochettino
With Spurs again slipping up in the Premier League race, Mauricio Pochettino wouldn't be blamed for considering his options.
That's an issue Pochettino wouldn't have to worry about in Madrid with the Argentine likely to be given the power to completely rebuild the squad.
Pochettino has conceded in the past if Madrid were to call, he'd have to listen. The big question, however, is whether Spurs would consider answering seeing as they have the coach contracted until 2023. Another consideration is the interest of Manchester United, who are yet to appoint a permanent successor to Jose Mourinho.
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#4 Antonio Conte
The front runner to replace Julen Lopetegui, Antonio Conte will again be in contention should Solari get sacked.
Still without a job after being dismissed by Chelsea in July 2018, the Italian revealed one of the reasons his move to Madrid likely fell through was his desire to have a full pre-season to work with.
"Real Madrid? For the type of coach I am, I preferred and prefer to wait for June to find a new job," Conte told the press in November last year.
While June is still some months away, another call from Real could be enough to convince him to jump back in now and allow him to fully assess how to rebuild a squad still reeling from Cristiano Ronaldo's departure. If not, Madrid could wait until the summer to appoint the right man - be it Conte or someone else.
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Real Madrid club legend Raul has been increasingly linked with succeeding his former team-mate Santiago Solari in recent days.
As a player, Raul is remembered as one of the greatest players in Madrid's history. He is the club's all-time highest appearance maker and was also Real's top goalscorer until he was surpassed by Cristiano Ronaldo.
Having only just taken over Real Madrid's Juvenil B team - winning his first game in charge - it would certainly be a gamble to appoint the 41-year-old.
However, president Florentino Perez would hope that his knowledge and understanding of the culture of the club would go a long way to helping him impress.
#6 Fernando Hierro
A Madrid legend and a former assistant coach at the club, Fernando Hierro lives and breathes Real and would immediately be a fan favourite if he came back to the Spanish capital.
The Spaniard has been linked with the Madrid job in the past and now might be the time for Florentino Perez to hand him the keys.
No stranger to Real as both a player and coach, the 42-year-old is currently the assistant manager of Turkish club Besiktas.
Guti previously led Real Madrid's youth side Juvenil A for two years where he was incredibly successful, winning the domestic treble during his first season.
Like Hierro, Guti is a club legend which counts for a lot in terms of respect from fans and players.
Would be a gamble similar to the appointment of Zidane, but that throw of the dice definitely paid off!
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#8 Zinedine Zidane
Speaking of Zizou, is there any chance he could return to Madrid less than a year after walking away?
Having seemingly bowed out at the perfect time, it's hard to see Zidane stepping back into a role that would take some serious work - but he could be exactly the man to right the ship.
Madrid would certainly welcome his return but he may take some convincing.
#9 Arsene Wenger
A romantic if
unrealisticoption for Los Blancos.
The former Arsenal boss all but ruled out any future move to Madrid in February revealing he's been a long-term target for the club.
"I turned Madrid down more than once but now I must say it's over for me," Wenger told beIN Sport.
Wenger, now 69, remains without a job, however, and hinted in 2018 he wanted to find a club quickly in the new year.
The Frenchman has previously admitted his love for Real as a kid and one final call could be all that he needs to be convinced to finish his managerial career in Madrid.
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#10 Joachim Low
A name that has and likely always will be thrown in the ring for the Real Madrid job.
Low looks determined to put a disastrous World Cup behind him and has set his sights on ushering in a new generation of German talent.
The 59-year-old has been in charge of Germany's national team since 2006 however and could be tempted into a return to club football with the right offer.
As a World Cup winner, it would be a surprise if Madrid didn't have him on their shortlist.
#11 Claudio Ranieri
It would be an extraordinary turn of fortunes for Ranieri, who was never really given a chance to implement his style at Craven Cottage, but crazier things have happened - Leicester City winning the Premier League for example.
Considering he was able to turn the Foxes into Premier League winners, it would be interesting to see what he could do with Real as they currently are.
Ranieri may be a long shot, but having coached over 1000 games, his experience can't be questioned.
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#12 Mikel Arteta
Mikel Arteta very nearly became Arsenal manager last summer and a move back to his home country may be in the works before long. Arteta has spent the last few years learning from Pep Guardiola at Manchester City and if he has picked anything up from him he could become an incredible manager one day.
As a student of Guardiola, Arteta would likely promote an attacking possession-based style which would please Madrid's very demanding fans.
One sticking point, though, could be Arteta's history as a player with Barcelona.
#13 Clarence Seedorf
Among the candidates to replace Lopetegui, Seedorf was ultimately overlooked but clearly still has his eyes set on coaching them one day.
“The fact that I have been among the options is already a great honour for me," Seedorf told Goal in March.
"I feel like a place that is my home, where I wasn't treated good, but more than good. Always.
“Returning one day would be an honour for me..."
Seedorf was appointed Cameroon's manager in August last year but has won just one of his first five games in charge.
He began his coaching career with AC Milan in 2014 and despite impressing was replaced by Filippo Inzaghi after just four months.
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#14 Jurgen Klopp
Widely considered as one of the best coaches in the world, Jurgen Klopp is exactly the kind of Galactico appointment that would help Real Madrid re-energise the dressing room.
A man motivator as well as a tactical genius, he has turned Liverpool into genuine title contenders for the Premier League following the Reds' impressive journey to the Champions League final last season.
Klopp would be an expensive option for Madrid due to the fact his contract at Anfield runs until 2022. However, Klopp is fully aware that there is likely to be speculation over his future this summer even if he can bring silverware back to Merseyside.
"In the summer, there will be people who say it's the best time for me to go if we win something because we will never win anything again, there will be other people who say I have to go if we don't win anything," he told Sky Sports in December.