The England international, 29, was decisive in City’s quarter-final victory over Paris Saint-Germain, repelling a Zlatan Ibrahimovic penalty in the first leg and keeping a clean sheet in the second as City reached the last four for the first time.
As one of only three players to have known life before the club’s Emirati takeover in 2008 -- Pablo Zabaleta and captain Vincent Kompany being the others -- he is particularly sensitive to the effect that European success can have on City’s international standing.
“You’ve got to do well in Europe to get that label (of a big European club),” says Hart, whose side host Madrid in the first leg of their semi-final on Tuesday.
“It’s a really difficult tournament, but we’ve got to believe we can win it. Otherwise there’s no point in turning up.”
Following successive group-phase exits and then two consecutive last-16 eliminations at Barcelona’s hands, Hart is a member of a core group of City players -- along with Kompany, Yaya Toure, David Silva and Sergio Aguero -- who have led the club into new European territory this season.
In doing so, the strapping blond shot-stopper has advanced his cause to be regarded alongside Bayern Munich’s Manuel Neuer and Juventus veteran Gianluigi Buffon as one of the greats of modern goalkeeping.
For despite two Premier League titles, one FA Cup and two League Cups with City, as well as 57 caps for England, there is not yet wide consensus that his name belongs in such exalted company.
A City regular since 2007, barring a season on loan at Birmingham City in 2009-10, when Shay Given was in favour at the Etihad Stadium, Hart has had to fend off accusations of arrogance in the past.
Memorably, Andrea Pirlo’s explanation for his brazen chipped spot-kick past Hart in Italy’s Euro 2012 quarter-final penalty shootout win over England was that the grandstanding City man “had to get off his high horse”.
In 2013-14, Hart experienced the biggest low of his career to date when he was dropped by City manager Manuel Pellegrini for the best part of two months following a succession of spectacular blunders.
But he showed no signs of unease on his return to the team and finished the season with the Premier League’s Golden Glove, awarded to the goalkeeper who has kept the most clean sheets and which he has now won four times, as well as a championship medal.
The Champions League has at times been a steep learning curve for City, but playing against seasoned elite-level contenders has given Hart a chance to shine.
Against eventual champions Barcelona last season, he pulled off 10 saves in a 1-0 second-leg defeat at Camp Nou, which moved Lionel Messi -- whose penalty he had saved in the first leg -- to brand him a “phenomenon”.
“He saved everything,” said the awestruck Argentine, while Barcelona coach Luis Enrique described Hart’s display as “incredible”.
When City lined up against Juventus, last season’s beaten finalists, in September, Buffon said “you won’t think of a better goalkeeper in the world”.
Hart was close to impeccable against PSG in the quarter-finals, with a Peter Schmeichel-style starfish save to thwart Edinson Cavani late in the second leg serving to kill off the French champions for good.
Having seen Willy Caballero, his deputy in cup competitions, steal the headlines by saving three penalties in February’s League Cup final penalty shootout win over Liverpool, Hart has extra motivation to make a difference against Cristiano Ronaldo’s Madrid.
The Spanish giants’ last visit to the Etihad, in November 2012, saw them record a 1-1 draw that eliminated City from the competition.
Three and a half years on, City are a cannier, wiser team, but Hart remains the man to beat.
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