'Barca!' How Spanish football giants drove Roosters to title

"Barca, Barca, Baaarca!"

So goes the final lyric of one of European football's most famous chants.

And so goes the on-field catch-cry – speaking to Trent Robinson's desire of emulating the Spanish powerhouse's stunning success – that helped drive the Roosters' historic premiership defence.

The NRL titleholders arrived in the UK for Saturday's World Club Challenge via Barcelona FC and the famed $AU500 million Camp Nou facilities of the footballing giants.

Their four-day detour was about far more than taking in the sights – Barcelona's 11 training fields, blinding trophy room or "basic" away dressing rooms (not even the Roosters could get access to the home side's most private sanctum).

"The style of play that we incorporated into our play, into our Roosters DNA last year, there was a bit of Barcelona to it," Roosters prop Jared Waerea-Hargreaves says.

"It was a big reason why we went there, to go and experience what we've tried to create. Reconnecting on why we tried to do that last year.

"For me it painted a picture on why we were saying those things, thinking that way at certain times of a game. Over their period of success [Barcelona FC] took the game to another level.

"They believe in a style of play in both attack and defence and we're thinking along those lines.

"We would call 'Barca' in games. That was the name for it. Everyone knew what it meant and what they had to do. We actually trained for it, going to that next level.

"Everyone knew their role. I can't remember it being called in the grand final but definitely throughout the year, we would use it all the time during games."

Roosters hierarchy are wary of any public comparisons to Barcelona FC, whose eight La Liga titles in the last decade is only matched by its status as one of world sport's elite organisations.

On average, Barcelona's first team took home on average £10 million each in 2018, more than double the entire salary cap of two NRL clubs

But just because the Bondi club occupies a different atmosphere, it doesn't mean they can't aim to emulate professional sport's top echelon.

In total the Roosters have had over 40 staff and wider squad members on tour throughout Spain and the UK this week.

Seventeen-year-old playmaker Sam Walker is along for the ride with several other rookies, former Wallabies coach Michael Cheika and an army of football department staff.

Robinson's high-performance operators have met with Toronto Wolfpack among other Super League clubs, rugby union's Leicester Tigers and English football powerhouses Manchester City to trade information.

"We take interest in different things, and the idea of watching Barcelona was around their style of play," five-eighth Luke Keary says.

"Everyone knows how Barcelona play. We'd watch a few videos and it's cool to look at other sporting teams and admire how they do things.

"That's the other aspect of going to Camp Nou, getting an insight into how another elite organisation does things.

"It's cool to see a global organisation like this. Real [Madrid], Man United, Barcelona, Dallas Cowboys, those absolute superpowers. For an NRL team to go to Barcelona, and Paris the year before, I definitely don't take it for granted.

"It's very special. We've accomplished a lot together in the last 24 months, and these types of experiences make it so memorable."

As much as Barcelona has been a focal point of both the past week and their 2019 triumph, the World Club Challenge clash with St Helens doubles as the premiers' one trial before a March 14 season opener at Penrith.

Angus Crichton gets his first crack at left-centre, Kyle Flanagan his first run in the No.7 jumper.

Aware of the travel toll, the Roosters will modify training loads over the next two weeks to ensure the trip doesn't double down on them when the post-Origin grind sets in.

The chance to also defend last year's win over Wigan – and no side has ever won back-to-back World Club Challenges – is a reasonable starting point for yet another NRL title tilt.

"We're here to finish 2019, and part of that is about starting 2020 for us with our new faces and new team," Keary says.

"But this game is still a part of 2019. When you get the trophy it doesn't say 2020 World Club Challenge, it says 2019.

"So we're here to finish that season and finish it well, because that can help us come into the new season with some momentum."