Perhaps it's best to start with a message of hope for Arsenal. Many people expect Barcelona to knock the Londoners out of the European Cup over the next few weeks, but David Villa, the Catalans' €40m (£34m) striker, is not convinced. Shaking his head at the idea that his side are overwhelming favourites to reach the European Cup final at Wembley in May, he says: "You have one off-day in this competition and you go out."
What he doesn't say – and this is the daunting reality for the Gunners – is that Barcelona average one off-day every five months.
They were poor at the weekend and needed a late Villa goal to salvage a draw against Sporting Gijon; five months earlier they were beaten at home by Hercules in their only defeat so far this season, and five months before that, they were dumped out of the Champions League by Jose Mourinho's Internazionale. For the rest of the time, they have been sublime.
Since the start of the season they have scored 112 goals in all competitions and it says everything about their incredible attacking prowess that 28-year-old Villa – the joint top-scorer from the last World Cup, and the joint top-scorer in Spain's international history – is only the club's third leading marksman in all competitions this season.
It also speaks volumes about the man who once admitted his scoring obsession was like a sickness that his pass and assist rate has almost doubled this campaign as he has dovetailed perfectly with Lionel Messi and Pedro in Barcelona's attack.
"If there is a team-mate who is absolutely, 100 per cent in a better position than you then, OK, I'll pass it to him," Villa says. No one pops up in a better position more often than Messi.
The Argentine has 24 league goals for the season. David Villa has 15 but it is their shared La Liga record – along with Spain forward Pedro, who has 12 – that is perhaps most astounding. Barça's front three have scored 51 goals in the league – just five short of Arsenal's entire squad.
"There are players who do wonderful things on the football pitch ... and then there is Messi," says Villa, who takes up the position on the left of that front three to let the Argentine play in what the Spanish call the false centre-forward position.
"He is the best in the world. I said that before I came here and now I can say it with even more authority. I am just glad that now I can enjoy playing alongside him instead of having to suffer playing against him."
Messi's astonishing strike-rate – 24 goals in 23 games – is a product of the attacking harmony with which Barcelona now play. Zlatan Ibrahimovic's limitations meant he had to play through the middle, leaving Messi playing wide on the left for much of last season.
The Swede's double gave Barcelona a two-goal lead in the first leg last year against Arsenal. He also scored the only goal in the Nou Camp Clasico but he lacked the flexibility shown by Villa, whose willingness to sacrifice himself has made all the difference.
Coach Pep Guardiola said: "Villa has always been a goalscorer and he has kept that part of his game but it is his movement off the ball that is so important. He makes the runs that help open up the space for our midfielders to play in. He brings Iniesta and Xavi into the game."
In 32 games last season for Valencia, Villa played 754 passes. At Barcelona in the first half of the season he was already up to 550 passes. Messi is repaying the favour. Never before has the Argentine assisted so many goals – 16 so far this season – and eight of those have been for Villa.
The team as a whole has scored 71 league goals. The domestic competition may be weak at times but then playing against the same sides, Real Madrid had scored only 52 ahead of their match at Espanyol last night.
Barcelona are on course to smash the current record of 107 goals for a season held by John Toshack's Real Madrid and it is Villa's ability to fit into the system that orbits around Messi that is making it possible.
The reward for such sacrifice should come in the form of trophies this season. Villa has won just two Spanish cups in a career spent, more often than not, outside of the Champions League.
It's a poor return for a European and World champion and Villa could have taken the Premier League route to silverware. As the clock ran down on Valencia's precarious economic situation, Chelsea and Manchester City joined Real Madrid and Barcelona in the race to sign him.
He picks out Wednesday's opponents Arsenal as the place where he would perhaps have been most happy had he gone to England and does not hide his relief that he ended up at the club which was always his preferred destination.
"As a spectator I like the way Arsenal play with quick one- or two-touch football," he says. "Their style would have suited me well. I also had friends at Liverpool and from what I have heard from team-mates, players learn a lot when playing under Rafa Benitez, but that did not happen."
In the end when Valencia finally buckled and allowed their prized possession to leave, Barcelona were best-placed to make their move. "I got used to the stories that I was going to England," he says. "You work just the same on the pitch but you definitely get a boost when your future is sorted out and everything calms down. Now I can switch off when I walk off the pitch, without the rumours that I once had to put up with.
"I was lucky that when the moment came when Valencia had no choice but to sell me, Barcelona were in a position to bring me here. I wanted to play here and I have been lucky enough that they wanted me as part of this team and that they were prepared to pay a lot of money to make it happen."
Helping Barça reach Wembley for a repeat of their 1992 European Cup final appearance, when they won the trophy for the first time, would be one way to repay the club. "I remember the final very well," says Villa. "It was a glorious day for Barcelona but it was also a great day for the whole country – everyone was happy with the victory. Hopefully this year we can repeat history by winning another Wembley final."
He has already played Champions League football in London, facing Chelsea on two occasions, and is not surprised that all English representatives progressed into the knockout stages, even debutants Tottenham.
"They were at a disadvantage at the start of the competition," he says, "not having played in it before, but they got a couple of great games under their belt and that levelled the playing field straight away. You can't call their run a surprise because you only have to look at their team sheet to see how many very good players they have."
The likes of Chelsea, Tottenham and Manchester United may wait for Villa further down the line if he can get past Arsenal. Having suffered so many seasons out of the domestic spotlight he is just happy still to be on for a potential domestic treble. "It's perfect for a player to go into the crucial stage of the season and still be involved in everything. Competition after competition – it is what we prepared for back before the season started and now we can enjoy it," he says.
Team-mate Xavi Hernandez has been impressed by the way Villa has fitted in instantly: "It is not easy to adapt to this team but it seems as though instead of being here for six months, he has been here for six years," says the midfielder.
Manuel Preciado, the coach who now manages his hometown side, Sporting Gijon, is not surprised that at last Villa is where he should be. "You could see it coming," he says. "It is a measure not only of his ability but also of his character. People said the train had left the station when he missed out on a move to Madrid two summers ago. They said he would never get another chance. But he just carried on scoring goals. He got more than 20 for Valencia and then went on to top-score in the World Cup finals."
Villa reached the pinnacle of his international career with those five goals in South Africa. His post-tournament form compares favourably with the likes of Wesley Sneijder and Diego Forlan, who shared top-scorer billing. That could be because he is playing in a better team, but Villa's stubborn consistency has been the hallmark of his career even in lesser sides.
He carried his hometown club Gijon for two seasons, scoring 38 goals in 78 games. He then scored 32 in 73 games for Zaragoza before becoming the fifth-highest goalscorer in Valencia's history with tallies of 25, 15, 18, 28 and 21 across five bountiful campaigns.
Villa has scored at least 15 goals in each of his eight seasons in the top division. He is also the player who always gets sold on by clubs who lack the financial muscle to build success around his prolific finishing and, aside from those two Spanish Cups, he is a player who lacks the club silverware of so many lesser performers.
"There is no better striker anywhere in the world than David Villa," says the Spain coach Vicente Del Bosque.
Now at a club that won't sell him and where if he doesn't score, then Messi or Pedro probably will, he might just start collecting those club honours that his consistency deserves.
Villa in the sun
* Born on 3 December 1981 in Langreo in the north of Spain.
* Villa played for Sporting Gijon, Real Zaragoza and Valencia before joining Barcelona for £34m last May.
* He has won 71 caps for Spain, scoring 44 goals, making him the country's joint highest scorer, alongside Raul.
* Helped Spain win both Euro 2008 and the 2010 World Cup, finishing top scorer at both tournaments.
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