For years now, Barcelona have relied on one superstar above all others, with Lionel Messi the player that has glued the team together at Camp Nou - the Argentinian's very presence bringing a sense of calm.
But now there is another South American whose impact upon the team has been quietly telling, and the anticipated return to action of Ronald Araujo this weekend could have a major impact at a crucial stage of the season.
Araujo does not have a cachet anywhere near that of Messi, but his absence was sorely felt as Barcelona stumbled to painful defeats against Paris Saint-Germain in the Champions League and Sevilla in the Copa del Rey.
Thankfully for coach Ronald Koeman, central defender Araujo is fit again after the ankle injury he sustained early in the 3-2 win at Real Betis three weeks ago.
The 21-year-old Uruguayan has missed the past five games, and his value to the team has perhaps never been quite so glaring as during his absence.
He was also sidelined for a five-week stretch in the autumn, and the evidence is mounting to show that Araujo, when fit, is now key to Barcelona's success.
"Ronald has had a very good season," Koeman said on Friday, when he named Araujo in his squad for the LaLiga home game against Sevilla.
"He is young and has learned a lot, he has shown his quality and physique. It is important to have strong and fast people. He must improve his game with the ball but defensively he contributes many things."
Koeman must know the data that shows exactly what a difference Araujo can make for Barcelona.
In the 20 matches that Araujo has played this season, Barcelona have won 14 times, drawn four and lost just twice, but when he has been absent that win ratio has nosedived.
Without Araujo's involvement, Barcelona have won nine, drawn two and lost six of their 17 games - amounting to a win percentage of 52.9, down from 70.
There is a curious contrast to be drawn here with Gerard Pique, the longest-serving centre-back at Barcelona.
A knee injury kept the 34-year-old out for almost three months until he returned to action in the shocking 4-1 home defeat against PSG on February 16.
In the 13 games Pique has played this season, Barcelona have a modest record of W6, D3, L4. Without him, they have won 17, drawn three and lost four.
As Koeman says, Araujo "contributes many things" to his defence, but perhaps in the twilight of his career that applies increasingly less so in the case of club great Pique.