Man City 3-1 Porto: Sergio Aguero reaches 40 goals but can he be considered a Champions League great?

Another match for Manchester City striker Sergio Aguero, another goalscoring milestone to celebrate.

When the 32-year-old Argentina striker found the net with a penalty in Wednesday's 3-1 comeback win against Porto, it was for his 40th Champions League goal, with all but five of that haul coming for his current club.

Aguero joins an elite list of marksmen, becoming only the 14th player to reach that landmark since the competition was rebadged in 1992.

He has now hit a total of 255 goals in 372 games for City, extending his record as the club's record scorer.

But, while his phenomenal haul cannot be questioned, his wider impact on the Champions League is somewhat less convincing when you compare it to the company he is keeping at the top of its scoring charts - and not just because all but two of the players above him have won it at least once.

Aguero's raw numbers are not in doubt, starting with his consistency - since his debut in the Champions League for Atletico Madrid in 2008 he has taken part in the competition in 12 out of a possible 13 seasons, and scored at least once in each of them with an overall record that is better than a goal every two games.

Along with Lionel Messi, Cristiano Ronaldo, Karim Benzema and Robert Lewandowski, Aguero is one of only five players to score in every season between 2011-12 and 2019-20 - he and Messi are the only two to have already got off the mark in this campaign.

In terms of time taken, Aguero is the joint-sixth fastest player to reach 40 goals when you count his games played.

His efficiency can hardly be faulted either. Aguero rises from 14th to ninth in the rankings when you consider his goals-per-minute ratio, with a goal every 127 minutes.

This is hardly a surprise when you consider that domestically he leads the way in this regard above Alan Shearer and everyone else on the all-time Premier League list, with a goal every 108 minutes.

It is only when you scrutinise WHEN Aguero's European goals have come that his record begins to falter.

Of his 40 goals, 30 have come in group games and another eight in the last 16. He has managed only one in the quarter-finals or later - against Tottenham in 2019 - a statistic surely linked to City's struggles to progress past that point.

It is not solely the case that Aguero's frequent injury problems have denied him the opportunity to add to his tally in the latter stages - since 2016, City have played nine matches across four quarter-finals and one semi-final, and he has missed only two of them.

But he has played in far fewer of those games than most of the other names to have made it to the 40-goal mark.

And, for whatever reason, when he has got there he has simply been less effective than usual at a time when his team have arguably needed him the most, with his goals-to-minutes ratio dropping to one every 543 minutes during matches in the last eight onwards.

City's failure to win the Champions League or even reach a final is not Aguero's fault, of course, but it means that, like his club, he currently has a glaring omission on his otherwise illustrious CV.

At the moment, it feels like he is missing a defining moment in Europe to match his famous strike against QPR that brought him the first of his four domestic league titles with City in 2012.

His greatest contribution for City in the Champions League so far is probably his group-stage hat-trick in a dramatic comeback win against Bayern Munich in 2014, rather than any of his nine goals in the last-16 onwards.

That is still enough to make him the joint 21st-highest scorer of knock-out goals, but they have either come in disappointing defeats against Barcelona, Monaco (two goals) and Spurs, or in what must go down as less than momentous victories over Dynamo Kiev, Basel and Schalke (three goals).

It feels like a slightly underwhelming showreel for a player of his ability and, while there is still time for Aguero to put that right and create a more meaningful European legacy with an iconic night of his own, maybe it is running out.

He is out of contract next summer and this season could be his last chance to cement his status as a true Champions League legend.

One way of doing that would be by finally getting his hands on the famous trophy, but can he help City make it to the final in Istanbul by maintaining his scoring rate this time?