There are three good reasons why Arsenal will feel they should make the most of their first leg at the Emirates tonight – Pep Guardiola has never won the away leg of a two-legged Champions League knockout tie; Lionel Messi has never scored in England; and Carles Puyol will not be on the pitch.
The Messi and Guardiola statistics are circumstantial – it is Puyol's absence that most advances the case that making the most of tonight's home game represents Arsenal's best chance of progressing. Barcelona have failed to win only nine games this season and in seven of those Puyol has been missing.
As Spain's tabloid press go in search of intimate photographs of Gerard Pique and Colombian pop star Shakira, with whom he is rumoured to be in a relationship, the only picture most Barcelona fans want to see at the moment is one that has Puyol with his arm around the Barcelona defender in a pre-match team photograph. The team's heroic captain has been missing since he suffered a bout of tendinitis in his left knee three weeks ago and has not travelled to London for tonight's first leg.
With Pique's off-field distractions beginning to affect his performances, Puyol would have provided a steadying influence against an Arsenal forward line led by a reinvigorated Robin van Persie, feeling tonight is their best opportunity to really hurt the Spanish champions.
Puyol, nicknamed "Captain Caveman", is the rock on which Guardiola has built two and a half years of unprecedented success. With all major honours now won, the 32-year-old has lost some of his powers of physical recuperation but none of his influence on the team. The central defender's absence from Barça's weekend match at Sporting Gijon was again key as they looked slow and disjointed in a disappointing 1-1 draw.
Asked afterwards if the performance had offered yet another clear indication of how much they rely on Puyol's athleticism and concentration, Guardiola's prickly answer spoke volumes. "We miss him, but we also miss Jeffren," said the Barcelona coach, naming his injured reserve winger in the same breath as his captain. He knows full well that there is no comparison between a useful reserve and the heartbeat of his defence.
When Barça conceded against Sporting, both the creaking Gabriel Milito and Pique were left trailing in David Barral's wake as the young striker raced clear to shoot past Victor Valdes.
Being man-marked by Spain's paparazzi, desperate for that first intimate shot that would confirm Shakira as his new partner – a pairing of Posh and Becks proportions – Pique could be forgiven for being slightly distracted. In the past he has made no secret of his tendency to take his eye off the ball and Puyol's steadying influence.
"It's great playing alongside him; he shouts at me the whole time," Pique said back in 2009. "He doesn't allow me to lose my concentration, not even for a second. It is impossible because I always have the same song behind me: 'Geri Geri Geri.' I'll turn around and say to him, 'what's up?' and he'll say 'nothing, just stay awake'."
Pique has emerged as the most complete defender in football since making those comments but he is still a better player with Puyol shouting in his ear and tonight, one yellow card away from missing the second leg through suspension, the absence of Puyol will be felt more than ever.
The midfielder Xavi highlighted Puyol's importance recently saying: "He may not be the best technically but physically he is spectacular and he is a great defender," and every time the midfielder and his Barcelona team-mates Messi and Andres Iniesta were asked about their recent triple Ballon D'Or nominations they name-checked Puyol first when they listed the club and international team-mates who could easily have joined them on the podium.
"We have won with him and without him," said Guardiola on Saturday night. "He is important for us but his absence does not explain the fact that we did not win this game."
Pique had to endure songs from the stands about his apparent new girlfriend, as well as one from the Colombian pop star herself, as Sporting Gijon mischievously blared out "Waka Waka (This time for Africa)" on the stadium sound system as the players warmed up.
He also had Milito alongside him at the weekend. The Argentine has all Puyol's experience but several serious knee injuries have left him with none of the mop-top one's mobility.
Milito will not play tonight. Eric Abidal will be drafted back into the side after being rested at the weekend and the protective shield provided by defensive midfielder Sergio Busquets will also be back in place. Abidal has been in excellent form this season and the fact that Guardiola chose to let the pair rest ahead of this fixture shows how important both the Frenchman and Busquets have become.
But although Abidal playing in the middle solves one problem, it may just create another because it means the former Internazionale defender Maxwell will play at left-back. The Brazilian excels in attack but can be compromised defensively and was run ragged by Theo Walcott this time last year. Barça are very wary of Arsenal's pace and what it could do to a defence not marshalled by Puyol.
In his weekly newspaper column, Johan Cruyff highlighted the "turbo-powered engines" of players such as Walcott and Andrei Arshavin and urged Barcelona players to "run down their fuel levels" by ensuring they spend most of tonight's game chasing the ball instead of in possession of it.
Puyol trained alongside Jeffren yesterday and Barcelona are confident he will be fit to play the second leg on 8 March. His return for the Nou Camp game is one reason for Arsenal to make the most of the Emirates leg; history throws up those other arguments for going for broke this evening.
Messi has played six times in England but failed to score, drawing blanks three times against Chelsea as well as in games at Old Trafford, Anfield and the Emirates last season.
And despite winning the competition in his first year as coach and reaching the semi-finals last season, Guardiola has drawn five and lost two of his knockout away legs, never chalking up a victory. He was beaten 1-0 away to Wisla in his first year in the preliminary rounds and went on to draw with Lyons, Bayern Munich and Chelsea in the knockout phase before winning the final in Rome against Manchester United. Last year, Barça drew away legs against Stuttgart and Arsenal before losing 3-1 to Internazionale.
Arsenal must take full advantage tonight. Guardiola and Messi will be back on home soil in three weeks' time... and so will Puyol.