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Based on Tuesday's evidence, scoring at least once at Santiago Bernabeu will not beyond Real Madrid. They countered an onslaught from Manchester City impressively to emerge just one goal down after a breathless 4-3 first leg. The issue for Carlo Ancelotti's men is going to be keeping Pep Guardiola's insatiable side at bay, as simply praying to catch the Citizens on an off day no kind of a plan to win a Champions League semifinal.

City now go to Madrid a goal to the good in the UEFA Champions League semifinals after a wild opener at Etihad Stadium and it could easily have been over before it even started. Kevin De Bruyne struck first as the hosts wasted little time getting going before Gabriel Jesus doubled that lead with barely 11 minutes on the clock. Real looked a shambles at that point.

Karim Benzema got the visitors back in it just after the half hour, but Phil Foden restored City's two-goal lead early in the second half only to be swiftly pegged back a goal by Vinicius Junior's superb jet-heeled solo effort. Bernardo Silva spectacularly re-established the two-goal cushion entering the final quarter of an hour and then Benzema cut the deficit again from the penalty spot with a sublime panenka.

After so much scoring in the first leg, key to those return hopes for Real will be Casemiro who was unable to even make a substitute appearance having recovered from injury sufficiently enough to at least make the bench. The Brazil international remains a key piece for Los Blancos, and at least two of City's goals could have been avoided with his vigilance.

Casemiro, now 30, is at least two years younger than regular midfield partners Toni Kroos and Luka Modric so not yet in his twilight years like many of his other teammates, or at the very least not as far into them. The balance that he brings to Real's midfield is inimitable and his presence would certainly have helped to avoid the quickfire efforts which arguably cost the Spanish giants this game, but not the overall tie.

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Ferland Mendy was at sea for De Bruyne's opener but went on to grow into the match with two assists, first for Benzema and then Vinicius, while the Belgium international and Bernardo scored from what were essentially midfield berths in Guardiola's setup -- something Real were unable to break up without Casemiro.

Ancelotti has shown his experience and cunning in recent weeks as his team close on the title in La Liga and perhaps not risking the midfielder here will ensure that he can be as fit as possible for the second leg knowing that he does not need to be forced into heavy action in the league either.

Maybe the South American's absence contributed towards the wild goal fest we were treated to in Manchester so we should not wish for a destroyer to be back in action and likely to limit the goals in Madrid. However, for Real to stand a chance at progressing over these two legs against City, they need the bite which Casemiro brings and his ability to break up their opponents' lethal attacks as they pour forward with precision.

As Paris Saint-Germain and Chelsea have already found out this knockout phase, this Real side is an unpredictable beast, but all beasts need a strong spine, and Real's is Casemiro at the base of midfield.