Ernesto Valverde sprung a surprise by selecting Arturo Vidal in his starting XI against Liverpool on Wednesday evening, yet the Chilean was Barcelona's warrior.
He ended up as one of the team's best performers at the Camp Nou, his last ditch tackle on Sadio Mane allowed the hosts to keep their clean sheet in the dying seconds of the match.
Having lived through a mixed debut season in Catalonia, the former Juventus star played his best game for Los Cules at the most opportune moment.
One of the concerns for Barcelona heading into the match was just how intense Liverpool's pressing game would be, yet Vidal was installed to battle against that.
Amongst the finesse of Sergio Busquets, Gerard Pique and Ivan Rakitic, it was Vidal who was the rough edge who approached the first leg of the semi-final like a man possessed.
He ran and ran and ran, putting Liverpool's own midfield under the huge pressure that they've been accustomed to watching, rather than being on the receiving end of.
"Arturo is having a great end to the season, he's been key in matches like this," Valverde explained in his post-match press conference.
"Opponents like this don't allow you to dominate the game, but we wanted to take advantage of Vidal's fitness.
"We had no doubts about him."
Barcelona were too passive in their embarrassing defeat to Roma in the former Athletic Club coach's first season, and a player of the Chilean's style didn't allow the Catalan giants to repeat such a failure.
The summer signing from Bayern Munich has added something unique to the Barcelona squad, and it's exactly why he's played almost 3000 minutes this term.
His 48 appearances have shown himself to be a complete juxtaposition to the club's other midfielders, but perhaps that's what Valverde needed for his system to work in the Champions League?
The Spanish coach isn't as unique as Pep Guardiola in his attacking style, and has been the subject of intense criticism because of that, however few can doubt he knows how to get the best out of players such as Vidal.