"Small details" has become Rafa Benitez's catchphrase in the four years since he began mastering the intricacies of the English language. Like any manager, however, he reluctantly accepts that some of those details – often the most crucial ones – will ultim-ately be outside his control. For all his exhausting arm-waving and shouting in the technical area, if a Liverpool defender tries to head the ball clear instead of trustinghis right foot to meet a low cross in the final minute, then all the planning in the world flies out of the Champions' League window.
Thus did John Arne Riise's aberration last Tuesday turn the semi-final against Chelsea if not on its head then at least on its side, allowing the London team an away goal that establishes them as the slightest of favourites for Wednesday's second leg. Until that day of reckoning, Benitez and Chelsea's less demonstrative leader, Avram Grant, will do what they can with the smallest details, before putting their fate in the hands of the chosen few.
With minimal shouted assistance from the sidelines, those performers must take responsibility and grasp opportunity. On these occasions, previous experience is an invaluable commodity, which is why in the likely absence of his fellow midfielder, the grieving Frank Lampard, Michael Ballack becomes such an important figure.
Despite his double strike against Manchester United yesterday, in the Premier League it is fair to say the German captain has not consistently achieved the standards expected of him when he signed from Bayern Munich in 2006. Yet in European competition he possesses historic stature as the only player to have reached the quarter-finals of the Champions' League with four different clubs.
First came unfashionable Kaiserslautern, who in 1998 won the Bundesliga the year after being promoted; a young Ballack helped them top their group the following season before being heavily defeated in the last eight by their compatriots Bayern. Next up were Bayer Leverkusen, with whomhe experienced his annus horribilis as a four-time loser in 2002, finishing runner-up in the German League and Cup, the Champions' League (to Real Madrid in Glasgow) and then the World Cup; Liverpool and Manchester United were among those he had put to the sword, scoring against both. Moving to Bayern that summer, he won three Bundesliga titles in four years while the club regularly faltered at the knockout stage, including a 6-5 aggregate defeat by Chelsea.
So to Stamford Bridge, where ankle surgery last March truncated a disappointing first season and kept him out until the Carling Cup victory over Liver-pool in December. There have been glimpses of his true form. Never has it been needed more than this week. All that experience of the competition tells him that Chelsea's late goal at Anfield, while a huge bonus, guarantees nothing.
"If you consider the result then we're a little bit favourites because we play at home, we scored an away goal. But we know Liverpool are a strong team away. Nobody thinks we are in the next round. They can score away as well, they have strong strikers with Torres and Kuyt, and Gerrard behind. They can play counter-attack and have shown especially in the Champions' League that they're always dangerous. Liverpool has a big tradition, but we play now, in this age and in this time. We can make history now. Chelsea have never been in the final and it's our motivation."
For Liverpool, the spotlight will unmercifully be thrown on two players who were below par in the first game: Steven Gerrard and Fernando Torres. Gerrard will be more aware than his new team-mate of Liverpool's shocking record at the Bridge, where they have not scored in an extraordinary run of eight games dating back to January 2004.
But Gerrard insists: "History will go out of the window on the night. We will give everything we've got and know that every player will have to put in a big performance if we are to do it. But we've done it before. We'll go there with a belief and confidence we've built up against teams like Milan, Juventus and Barcelona. Even though we have now drawn three times with Chelsea this season, in two of the games we were very much the dominant side."
Gerrard or Ballack? Torres or Didier Drogba? Small details and big players will decide whowill be playing in Moscow on 21 May.
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