Why Sergio Aguero Is Manchester City's Crucial 2014-15 Champions League Player

Manchester City have aggressive, ambitious Champions League dreams. But the Sky Blues will probably only go as far as Sergio Aguero can carry them.

As currently constructed, City certainly do not project to defend their way to a Champions League crown.

City goalkeeper Joe Hart is again the subject of rumors surrounding his job security (or lack of same). 

"Hart’s position seems to have been under constant review for the past two seasons or so," wrote Jamie Jackson in The Guardian recently. "The 2012-13 failed championship defence featured him being questioned by Roberto Mancini, the manager at the time."

Mancini's successor is no great Hart defender, either. Jackson quoted Pellegrini thus: “In this moment I’m playing Joe Hart but he [Willy Caballero] will have his opportunity soon.”

Delightful.

So if the goalkeeper is iffy, how is the line in front of him? Um, don't ask.

Vincent Kompany is his usual dependable self, but beyond him are a series of question marks that sides like Bayern Munich and CSKA Moscow probably cannot wait to provide the answers to.

Pablo Zabaleta is out for City's first match with Bayern Munich after seeing red against Barcelona last season. Zabaleta, like Pellegrini, will have to take in this match from somewhere other than the pitch. So Bacary Sagna will probably be thrown into the deep end of the pool against Bayern.

Summer signee Eliaquim Mangala, thought to be the antidote for Martin Demichelis' lack of pace, still has not played for City. Mangala's ongoing absence has emboldened Demichelis to ask for a contract extension, per David Anderson in The Mirror.

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So Kompany will anchor the defense against Bayern next to either a player he has never played with before or a player with whom he has failed spectacularly in the past.

The defensive hope in the midfield is, for now, also on ice. According to Stuart Brennan in the Manchester Evening News, "City's game plan for Bayern Munich has already been ripped up by injury to Fernando."

Yaya Toure and Fernandinho are fit, but Toure has offensive responsibilities that largely preclude the giant Ivorian staying home on defense for 90 minutes.

While it is loads of fun watching David Silva, Samir Nasri and Jesus Navas go forward and create, it is quite a bit less fun watching them try to track back against physically larger players.

If City cannot defend their way to this prize, they will have to score themselves onto the podium. Given Alvaro Negredo's departure and Stevan Jovetic's recurring inability to stay upright, though, City are down to two healthy strikers: Aguero and Edin Dzeko.

Dzeko has started the season brightly in terms of the quality of his play, but he is also goalless through four league matches. Besides, if City rely on the 4-5-1 Pellegrini likes to employ in matches against equal and superior competition, only one of the strikers will start anyway.

Rui Vieira/Associated Press

It will almost surely be Aguero.

Right, so you are saying that all of the foregoing concerns are only temporary. Zabaleta's suspension is only for one match. Neither Fernando nor Jovetic are lost for the season. Mangala will be fit soon enough and make the haunting sight of Demichelis trying to mark elite scorers go away. It will all be fine, you say.

Will it, now?

If the last three Champions League campaigns taught City supporters anything, it is that this tournament is unforgiving and unpredictable. City can only safely predict that where some players' fitness will improve, others' will fail.

Plus, the goalkeeping situation projects to evolve in the coming months. City do not have the luxury of running Manuel Neuer out there night after night.

With apologies to Kompany and Silva (and perhaps Toure), the one player City probably cannot survive even the Champions League group stage without is Aguero.

Because City have to score in bunches to survive this newest Group of Death, and Aguero needs to be the one to provide them.