See Kaka tie Walter Samuel in knots with his dribbling skills

Arsenal beware. Kaká, too, has put a man out of football for the rest of the season. However, unlike Martin Taylor, of Birmingham City, whose foul tackle finished Eduardo da Silva's involvement in this Champions League campaign, the World Player of the Year achieved it not nefariously but by playing the game as beautifully as can be imagined.

When Liverpool walk in Arsenal's footsteps to the San Siro a week today, they will play an Inter Milan team who are without Walter Samuel, the Argentina defender. Kaká is the reason for that.

On December 23, when Inter played Milan in what Italians call the “Derby della Madonnina” after a Milanese landmark (the statue of the Virgin Mary on top of the Duomo), Kaká attacked his opponent so fairly yet so directly and effectively that Samuel required reconstructive surgery on a cruciate ligament. He is not expected to feature for the club again until the 2008-09 season.

Viewed now, even without the emotion of the occasion, it remains a remarkable sequence, Kaká picking up the ball just inside Inter's half on the right and setting off at speed on a diagonal inside run before checking to go outside again and, on the edge of the penalty area, altering his direction to come back in. It is at this point that Samuel's left knee decides that it has had enough and he staggers, helpless, before falling to the ground. An attempt to get up is swiftly aborted - while Kaká has turned his back to goal and is playing a one-two with Clarence Seedorf - and as Samuel begins signalling for help, Kaká is rugby-tackled to the floor by Esteban Cambiasso, the Inter midfield player.

If television companies decided to censor this piece of footage to protect the delicate sensibilities of viewers, they would be doing the sport a disservice. It is almost poetic; Kaká's brilliance reducing the player known as The Wall to rubble.

Small wonder that Arsène Wenger, the Arsenal manager, sees cutting the supply line to Kaká as crucial to his ambitions in Europe this evening. It is not only Kaká's talent that Arsenal must stifle but also his propensity to rise to the occasion in the biggest matches. Like all the greats - and as a winner of the World Cup, the European Cup, the Brazilian and Italian league titles, plus player of the year awards from Fifa and Uefa and Serie A footballer of the year trophies on two occasions, Kaká fits that category - it is when the stakes are highest that he excels.

If the Champions League is the finest form of expression in club football, Kaká is its shining star. He has played all 630 minutes of Milan's Champions League matches this season. In 2005, he was voted best midfield player, in 2007 best forward and last season he was the top scorer in the tournament, despite playing behind Milan's main striker. When Manchester United visited the San Siro, it was Kaká's match-winning display set against the anonymity of Cristiano Ronaldo that convinced many that the Portuguese had a few more step-overs to take before he could be acclaimed the world's greatest footballer.

“Right now, Cristiano is playing very, very well,” Cesc Fàbregas, the leading light of Arsenal's midfield, said. “But over the last two seasons Kaká has been the best without any doubt.”

Carlo Ancelotti, the Milan coach, compares Kaká to Michel Platini, Pelé thought that he was more like Johan Cruyff, Zico put him beside Socrates. Wenger believed no superlative too extreme, citing Kaká as the master of Champions League football, the embodiment of Milan's success.

“The best players perform on the right occasions and Kaká has shown he can do that,” the Arsenal manager said. “His performance in the Champions League made it impossible to argue when he received the Ballon d'Or [for European Footballer of the Year]. Last season he scored ten goals in 11 games, this year he made the difference in Milan's matches with Celtic, just as he is the difference in so many matches in this competition.

“When Kaká gets the ball, Milan achieve this sudden acceleration that can kill you. We are aware of his talent and will have to deal with it as best we can.” As Samuel will verify, that is easier said than done, particularly if Kaká sniffs the atmosphere of the occasion and decides it is going to be his night.