Updated at 12.00

Real Madrid v Atletico Madrid, Kick off: 7.45pm, San Siro

1. Can Ronaldo deliver definitive performance?

THERE IS NO doubt that Cristiano Ronaldo is one of the greatest footballers of all time, and he is perhaps the most clinical goalscorer ever to play the game.

Yet, despite registering over 50 goals for the sixth consecutive season this year, even someone as impossibly talented as Ronaldo is not perfect.

In seven seasons at Real Madrid, he has won four major trophies — one La Liga title, two Copa del Reys and one Champions League. By most players’ standards, that’s a pretty impressive list of achievements, but for a player of Ronaldo’s astronomical aspirations and ability, the superstar has arguably underachieved slightly in this regard since coming to Spain.

For all Ronaldo’s individual genius, there also remains a lingering suspicion that he should be much more of a team player, helping fellow attackers Karim Benzema and Gareth Bale in the way Barcelona’s Lionel Messi seamlessly turns Luis Suarez and Neymar into better players.

Moreover, in one sense, Ronaldo’s greatest moment in a Madrid jersey, the 2014 Champions League final, was hardly befitting of his magisterial brilliance. Granted, the Portuguese international scored a last-minute extra-time penalty, but at that stage, his team had the match wrapped up and the game was long since over as a contest, with Carlo Ancelotti’s men triumphing despite their main man looking half-fit and well short of his best throughout proceedings.

On Saturday night, however, Ronaldo has a chance to enhance his legacy. Another Champions League winners’ medal would be further confirmation of his greatness, as well as undermining those expressing reservations about his somewhat underwhelming trophy haul in recent years.

There have been doubts about the 31-year-old’s fitness ever since he picked up a hamstring injury against Villarreal in April, but if anyone can overcome such worries, it’s the three-time Ballon d’Or winner.

2. Will the best defence in Europe be toppled?

Diego Simeone has moulded his side into a formidable defensive unit. Matthias Schrader Matthias Schrader

It’s hard to argue with the widely-held belief that Atletico Madrid possess the best defence in Europe.

It’s hard to think of any team in the world right now that are better organised without the ball than Diego Simeone’s men.

Moreover, their collective ability at the back is what shines true rather than the brilliance of any one particular individual — a true testament to the coaching prowess of former Argentina international Simeone, as well as the absence of inflated egos within their set-up.

For instance, some critics feared for Atletico when defensive stalwart Diego Godin was ruled out through injury ahead of their semi-final first-leg with Bayern.

Nevertheless, even without the acclaimed Uruguay international, Atletico emerged with an impressive 1-0 win against the much-fancied German outfit, as their backline looked as strong as ever.

And the stats certainly back up these claims of immense defensive solidity — in total this season, they have kept 35 clean sheets, and conceded just 18 goals in 38 La Liga matches, equalling the all-time record in Spanish football in the process. Moreover, in the Champions League, they have earned clean sheets in 15 of their last 21 matches.

For all Madrid’s star power in attack, Atletico’s patently greater cohesiveness and discipline in defence will likely make it an often frustrating and mentally exhausting evening for Zinedine Zidane’s side.

3. Will previous matches between the two be in the back of players’ minds?

Many people are citing the 2014 Champions League final as an integral part of the narrative to this game — two years ago, Ancelotti’s Madrid side prevailed 4-1 after extra-time — but Atletico actually have a superior overall record to Real in recent times.

In the last 16 matches between the two teams, Atletico have won seven, drawn five and lost only four.

On the other hand, Real are the historically bigger club — they are bidding for their 11th Champions League/European Cup, while despite two final appearances prior to this season, Atletico have never lifted the trophy — so Los Blancos will be slight favourites in Milan tomorrow night.

The game is expected to be extremely tight with a lack of space for creative players to flourish, which will undoubtedly suit Atletico more than Real — in the last four matches between the teams, both sides have scored two goals apiece, so it seems unlikely that Saturday night will buck this trend.

Some critics have suggested, though, that the heartbreaking 2014 loss could impact on Atletico psychologically, yet this claim seems contentious at best.

It’s difficult to imagine any side managed by the uncompromising, warrior-like Simeone being prone to mental fragility, while just six members of the 2014 squad are still with Atletico now, so it’s hardly likely to be a major factor in deciding this encounter’s outcome.

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