As Barcelona resumes Champions League play, it also continues pursuit of an impossible standard

Once again, FC Barcelona sets out on the long and treacherous slog toward a sixth Champions League title. The drought, such as it is, now stretches into its fourth season. And the Catalan juggernaut has won it just once in the last seven campaigns, following two European crowns in just three years.

For any other club, a haul of three Champions League titles in a decade would be considered a golden age. There are, in fact, only six clubs in the world who have won it more often than that in their entire existence. And we very much are at the high point of Barca’s 119-year lifetime. Seven La Liga titles and six Copa del Rey trophies in a decade, in addition to those three European championships, speak to the way the club has not only dominated but remade the sport, reimagining the outer bounds of possibility.

Yet, somehow, unreasonably, impossibly, it also feels like the club has fallen somewhat short in European competition lately.

In the last three seasons, and in four out of the last five – wedged around the last winners’ medal – Barca stranded in the quarterfinal. It went out to Atletico Madrid for a second time in three years back in 2016. And then rather meekly to Juventus in 2017, after somehow overcoming a 4-0 deficit to Paris Saint-Germain in the previous round with an epic 6-1 comeback. And then finally, last year, to an unfancied AS Roma, in spite of Barca carrying a 4-1 lead into the return leg in Rome.

They were upsets all. Each time, Barca had the distinct look of a tournament favorite.

Tuesday arrives the beginning of Barca’s knockout stages in this year’s Champions League, after the drudgery of the group stage and the habitual re-setting after a two-month European hibernation. The Catalans travel to Lyon to take on Olympique Lyonnaise, the French club that’s become a perpetual also-ran as PSG devoured the French league whole. And Barca does so while facing down the daunting prospect of two Clasicos with blood-rivals Real Madrid in just four days next week – one the return affair in their Copa del Rey semifinals, deadlocked at 1-1, and the other in La Liga, where Barca could take a stranglehold on its lead.

Barca, as every year, is expected to win all these competitions. It isn’t the sort of club that gets to prioritize out loud, in the way that even mighty Liverpool, a Premier League contender and last year’s losing Champions League finalist, apparently can.

And it’s not been easy going of late. In its last four games, Barca struggled to a 2-2 home tie with Valencia, had to come from behind to tie Real 1-1, was a tad fortunate to escape Bilbao with a 0-0 tie against Athletic, and clawed its way to a 1-0 squeaker over Valladolid.

All the while, Real had been gaining in the league, until it spilt all three points at home vs. little Girona on Sunday.

Barca manager Ernesto Valverde readily acknowledges that his team is struggling through a slump of sorts – an undefeated one, at that, because at Barca’s towering heights, only lopsided scorelines count – telling a recent press conference that “sometimes you cannot be brilliant in every game.”

Defensive rock Gerard Pique predicted that Barca will “suffer a lot” against Lyon if it doesn’t improve quickly.

Lyon, for its part, is undaunted. Defender Kenny Tete certainly isn’t. “We’ve proven in big games that we don’t have to be scared of anybody,” he told Dutch magazine VI.

There’s enough of a precedent there, a long enough track record of Barca tripping up sooner than it ought to in the Champions League knockout rounds, that underdogs take heart. Barca has shown itself to be as fearsome as it is fallible.

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And so it suffers a bit too often at key junctures in the season, when it’s expected to be perfect. Leaving us to wonder what, exactly, the benchmark for this team ought to be. What should be the requirement of a team that’s been doing things for a decade that nobody had done before? That plays a mesmeric new style, transcending the sport until competitors slowly caught on? That revolves around a player so overwhelmingly superior to anybody who came before him, or to any of his contemporaries, that his name needn’t even be said?

Because this is the trouble: While Barca was busy reinventing soccer, Real was plodding its way to three straight European titles and four in five years, setting all manner of modern-day records. While poetry was composed for Lionel Messi and the peers he pulled into his near-earth orbit, Real won the biggest trophy in the sport again and again. And again. And again.

It’s not an asterisk behind this soaring Barca era, by any means. Three European titles satisfy the expectation on a dynasty just fine. But it does beg the question if FC Barcelona, anno 2008-09 to 2018-19, can be the best club team ever when, by perhaps the most important metric of all, it wasn’t quite the best team of its time.

Because when you’re as good as this Barca team is for as long as it has been, it’s never entirely enough.

Leander Schaerlaeckens is a Yahoo Sports soccer columnist and a sports communication lecturer at Marist College. Follow him on Twitter @LeanderAlphabet.

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