The sprinkling of supporters occupying their seats in time to see the teams warm up rose to applaud. Minutes later, Thierry Henry emerged, the glorious homecoming tainted by the fact Pedro Rodriguez was preferred in Barcelona's attack by coach Pep Guardiola.
Crowd pleaser: Barcelona's Thierry Henry applauds the fans at the Emirates Stadium
Henry was at his most nonchalant. He had sauntered into the stadium from the team bus in his club suit, embracing members of Arsenal's match-day staff and the giant dinosaur mascot on the way.
Ambling on to the pitch in his kit, he offered a little wave and flashed a winning smile as Cesc Fabregas put his head down and worked through the pre-match exercises with his team-mates, testing the injured knee which had threatened his involvement.
One man with Arsenal in his heart, no longer the force he was. Another, with Barca in his blood, fit to lead out the team in red and white. It set the pattern for a night to confuse the emotions.
El Capitan's presence may have lifted those inside an arena rarely famed for its atmosphere but he had his own reasons for making this one. Having made his first visit to the Nou Camp at the age of nine months, in the arms of his grandfather, Fabregas did not want to miss it.
Fifteen minutes later, he would have been doubting the wisdom of playing, as a breathless game pulsed quickly around him, too slippery for him to get a grip.
Barcelona's midfield trio pressed with incredible energy and aggression. Arsenal were stunned and Fabregas had the look of a man who had rushed his comeback. He wasn't the only one. After seven weeks out with a calf problem, William Gallas did not make it to half time.
On the ball: Barcelona's Thierry Henry tangles with Arsenal's Emmanuel Eboue and Abou Diaby
Fabregas failed to track back early as the yellow shirts swamped Manuel Almunia's goal, he was guilty of a poor touch as he tried to pull a ball out of the sky on the edge of his own box and he struggled to get on the ball and orchestrate the tempo as the visitors dominated.
Samir Nasri - not for the first time in recent weeks - looked set to be Arsenal's most creative force, only to fade as the tie appeared to slip out of reach, only for Fabregas to keep it alive with a late penalty he won and converted himself. He hobbled straight off, then back on again, and limped through the closing minutes. He could barely put his weight on his right leg after 93 minutes played in an exhilarating blur.
The damage done to him and Gallas may ultimately wreck Arsenal's bid to end their wait for a trophy, but Fabregas cannot play in Barcelona next week regardless of his fitness after a yellow card was harshly brandished in his direction.
He was booked just before half-time for a well-timed sliding tackle from the side. Fabregas protested as the teams left the field at half-time but, for him, there exists a kind of open invitation to sign up for this flamboyant machine at the Nou Camp; a team built to attack; a club he quit seven years ago. Add to this the lure of Guardiola, the dignified man in charge, whom Fabregas idolised as a boy.
One day, perhaps, he will make a return to his native Catalonia and wear Barca's No 4 shirt like Guardiola once promised he would. Why would anyone reject the chance to play football in this team, alongside his long-time pal Lionel Messi, that mesmerising exponent of close control?
The draw is strong but on the bench at the Emirates sat a reason to resist the greener grass of home. Henry, scorer of 226 goals in 369 games over eight seasons with the Gunners, has rarely reached such heights with his new club since signing for £16million three years ago.
He has 14 months left on a four-year deal and is likely to be on the move again in the summer. Guardiola cannot find him a regular place and he was largely ignored last night as he went through his stretches.
The game was too captivating to look away, even for a split second, to salute one of the greatest players to have graced the Barclays Premier League. Henry's name was sung briefly at the start of the game, his return for the last 15 minutes received a terrific roar and he was cheered from the pitch at the end, despite contributing virtually nothing to the game.
But there could be one final favour to perform for the club he served so well. Regular text traffic passes between the mobile phones of Henry and Fabregas and the Frenchman personifies how difficult and unpredictable a footballing transplant can be.
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