Real Madrid can cap their most successful year ever with victory in the Club World Cup final against Brazilian side Gremio on Saturday, which would see them become the first team to successfully defend the trophy and end 2017 with five titles.
Defeat, however, would be the latest of a series of setbacks in a haphazard last few months for Zinedine Zidane's side, who are fourth in La Liga, trailing leaders Barcelona by eight points in the standings.
At times, they have looked a shadow of the team that swept to Champions League and Liga glory last season and crushed Manchester United and Barca to win the European and Spanish Super Cups.
No South American side has managed to beat their European counterparts in the Club World Cup since Gremio's compatriots Corinthians stunned Chelsea with victory in 2012, although an upset is not entirely out of the question in Abu Dhabi.
Real only narrowly avoided a catastrophic defeat to Abu Dhabi side Al Jazira, who took a remarkable 1-0 lead at halftime in a chaotic, action-packed semi-final which the double European champions eventually won 2-1.
The Spanish side dominated the game but, not for the first time this season, showed remarkable profligacy in front of goal until Cristiano Ronaldo equalized in the second half and Gareth Bale hit a late winner 30 seconds after coming off the bench.
Real are sure to face an even sterner test from Gremio, although the Brazilians also had to battle their way through their semi-final, overcoming Mexicans Pachuca 1-0 after extra-time.
Gremio's coach Renato Portaluppi won the Intercontinental Cup (the forerunner to the Club World Cup) with the club as a player and underlined his reputation for courting controversy by recently proclaiming he was a better player than Real's Ronaldo.
The Portuguese, who was recently named the world player of the year for a joint-record fifth time, became the top scorer in the history of Club World Cup by netting for the sixth time in three separate tournament appearances.
The previous record of five was jointly held by Luis Suarez, Lionel Messi and Cesar Delgado.
Real were given an almighty scare in last year's final, falling behind Japanese side Kashima Antlers before eventually winning 4-2 in extra-time with the help of a Ronaldo hat-trick and Zidane said he expected another difficult final.
"I don't know the Brazilian league well but I watched their semi-final and they are a good team and we will have to lift our standard of play against them," Zidane said after the nervy win on Wednesday.
"It will be a complicated game because there's no such thing as an easy game, as we proved against Al Jazira."