Real Madrid and Barcelona share a rivalry so fierce in Spain that, if mistakes are made, it could spell the end of a player's career at either club.
The late Francesc Arnau and former Barcelona goalkeeper had to learn that the hard way in 2000, after conceding a piledriver of a free-kick from Roberto Carlos - who ranked at no.90 in FourFourTwo's list of the greatest footballers of all time. Five minutes into the match at the Bernabeu in February of the 1999/00 season, the Brazilian stepped up from a long way out to unleash a deadly strike.
Real Madrid eventually won the game 3-0, while Arnau didn't feature again for the rest of the season, instead having to spend the rest of the campaign on the bench as Barcelona manager Louis van Gaal preferred Dutch goalkeeper Ruud Hesp thereafter.
Real Madrid end Francesc Arnau's Barcelona career
“This was my first goal in El Clasico against Barcelona – it was obviously from a free-kick! I smashed the ball from 35 yards and Francesc Arnau couldn’t stop it," Carlos exclusively told FourFourTwo in 2022. "A few years later, I remember hearing him saying that it became a turning point in his career – after that goal, Louis van Gaal didn’t play him any more.
"Unfortunately, Arnau has since passed away and is no longer with us. That was a really memorable game for all of us. I had been especially motivated, because before the match I’d told journalists that Luis Figo would have to mark me this time.
"It was a bold statement to make, but it worked out for me. Until then, I didn’t have what you could describe as the best record against Barcelona [P7 W1 L4].
But while Real Madrid beat their bitter rivals in such convincing fashion, they eventually only finished the season in fifth place - though they did lift the Champions League trophy in May. Barcelona, meanwhile, came runners-up in La Liga to Deportivo la Coruna.
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Carlos' record against Barcelona didn't improve too much during the rest of his time in the Spanish capital, either. In 24 games he won seven, drew seven and lost 10, scoring just once more following his strike in 2000.
That second goal proved crucial, handing Real Madrid their first win at Camp Nou in a La Liga match for the first time in 20 years when they won 2-1 in December 2003.