Last year, Real Madrid won the UEFA Champions League after a close-fought final against fierce local rivals Atlético Madrid. The score was 1-1 after extra time, leading to a penalty shootout that finished 5-3 in Los Blancos’ favour. While Zinedine Zidane, who was only appointed manager in January, deserves credit for guiding a talented but under-performing side to the top honour in European club football, there remains a large question mark over whether this side can do what many great teams of yore failed to do and retain the Champions League.

The difficulties have started earlier for Zidane and company in the group stage, finishing second in Group F, winning only three of six games and conceding ten goals in the process. While Real Madrid are still second favourites to win the competition with 888sport going into the round of 16, some supporters and pundits will be reluctant to back them due to the ‘holder’s curse’ - no club has ever successfully-defended the Champions League since the competition’s inception in 1992.

It was relatively common for teams to retain its predecessor, the European Cup, several seasons in a row. Indeed, Real Madrid won it for the first five seasons from when it began - 1956-1960. Ajax won it three times on the trot between 1971 and 1973, and Bayern Munich repeated the feat between 1974 and 1976, while Benfica, Internazionale, Liverpool (twice), Milan and Nottingham Forest all won two in a row.

The knockout format of the latter stages of the tournament means any clubs chances of success are likely to be partially dependent on the luck of the draw. While detractors accuse the Champions League of being too predictable in the era of the superclubs, the fact is that seven different clubs from four different countries have won the Champions League over the past ten seasons.

Barcelona are the current favourites to win this season’s Champions League, with new signings Paco Alcàcer, André Gomes and Samuel Umtiti bolstering the Messi-Suárez-Neymar attacking trident. The club’s chances may soon be boosted further by manager Luis Enrique being able to concentrate his resources solely on the Champions League, with Barça already six points off the pace in La Liga.

Bayern Munich will feel they are due a Champions League final appearance, having made the semifinals for the last three seasons, and the German powerhouse has arguably the best defence in the competition in the shape of Manuel Neuer, Jérôme Boateng, Mats Hummels, Philipp Lahm and David Alaba.

Atlético Madrid improved an already impressive side with the addition of France striker Kevin Gameiro, while Gonzalo Higuaín, Miralem Pjanic, Dani Alves and Mehdi Benatia have added strength in depth to the BBC defensive trio of Andrea Barzagli, Leonardo Bonucci and Giorgio Chiellini. And the loss of Paul Pogba haven't led to doubts on the Italian team's chances.

Real Madrid will find this season’s Champions League a harder battle than the previous one, but they will be confident of making the quarterfinals having drawn a Napoli side having a patchy season thus far. As ever, the pressure is on, and despite their many strengths and luck, they will have to buck the trend of the past 25 years to retain their title. However, anything can, and often does, happen in football.

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