Will Hiddink play one at the back?
If you want to know whoÃ¢ÂÂll win the UEFA Champions League semi-finals, donÃ¢ÂÂt ask me.
Head to AlkmaarÃ¢ÂÂs cheese market and find the fortune teller who told Louis Van Gaal AZ would win the Dutch title on 19 April 2009. Van Gaal was sceptical Ã¢ÂÂ his team didnÃ¢ÂÂt have a game on that day Ã¢ÂÂ but PSVÃ¢ÂÂs 6-2 thrashing of Ajax on the 19 April gifted AZ the Eredivisie.
Instead of predictions Ã¢ÂÂ mine usually stink Ã¢ÂÂ I bring you stats...
Eight out of the last 10 semis have been decided by a goal or less on aggregate, and five of the last 10 sides to play the first leg at home have progressed.
The last reigning champions to reach the final the next season were Juventus in 1997. That was the last time a side (Borussia Dortmund) won the Champions League for the first time.
Dortmund triumph in 1997
This seasonÃ¢ÂÂs semi-finalists all broadly favour attack, play four at the back and look a bit dodgy in defence.
Pep Guardiola could have emulated his mentor Johan CruyffÃ¢ÂÂs 3-4-3 but wisely uses a better organised version of RijkaardÃ¢ÂÂs 4-3-3. BarcelonaÃ¢ÂÂs defence looks in the best nick, although Deco thinks they are too short as a unit.
For the record, Carles Puyol is 5ft10in, four inches shorter than ChelseaÃ¢ÂÂs Serbian not-so-secret weapon Branislav Ivanovic.
Battle of the 4-3-3 squadrons...
Pep Guardiola once said that Johan Cruyff created the chapel and it was every Barcelona coachÃ¢ÂÂs job to improve or restore it.
The one question vexing this smart, obsessive, skinny coach, who has done such a cracking job of sprucing up the Barca chapel this season, will be 'what trick does Guus Hiddink have up his sleeve?'
Surprise can be as effective a weapon in football as it was in comedy for Monty PythonÃ¢ÂÂs Spanish Inquisition.
HiddinkÃ¢ÂÂs Australia played one at the back against Japan in the 2006 World Cup (as the Socceroos recovered from 0-1 to 3-1). He has used 3-5-2 (at PSV in 1988), 4-4-1-1 (Holland, France 98), 3-4-3 (South Korea, 2002), and 4-3-3 (PSV 2005, when he terrified Milan in the semi-final second leg, and now at Chelsea).
He will probably prefer 4-3-3 against Barca. Coaches often like to mirror the opposing formation (daft as it sounds, it can confound the other team), but the BluesÃ¢ÂÂ 4-3-3 is designed to counter, while BarcaÃ¢ÂÂs 4-3-3 is all about keeping the ball and suffocating opponents, pressing so that Messi, Henry, EtoÃ¢ÂÂo can strike.
While the papers focus on Messi. Hiddink may scheme to stop Xavi, who initiates most attacks (although Iniesta scored one and had a hand in three against Sevilla).
As a coach, itÃ¢ÂÂs hard to legislate for MessiÃ¢ÂÂs genius. But if Chelsea can deny BarcaÃ¢ÂÂs skilful, industrious midfielder space Ã¢ÂÂ will Essien do to Xavi what he did to Gerrard at Anfield in the quarters? Ã¢ÂÂ they could isolate the forwards.
"It's my ball, and you're not having it"
Hiddink wonÃ¢ÂÂt ask Chelsea to sit back as United did against Barca. In a CNN interview, he says Ã¢ÂÂIn Europe, itÃ¢ÂÂs important to get some harm done in the away game.Ã¢ÂÂ
Especially as keeping clean sheets canÃ¢ÂÂt be taken for granted at the Bridge where set-pieces have become a concern. And, if we come to the last 10 minutes at home with Chelsea chasing the game, Hiddink will play one at the back Ã¢ÂÂ or something equally radical Ã¢ÂÂ if he sees fit.
In certain crannies of the internet, fans laughingly call Hiddink Ã¢ÂÂThe semi-finalist.Ã¢ÂÂ (He has only won one, with PSV back in 1988, losing with Holland in 1998, Korea in 2002, PSV in 2005 and Russia in 2008).
This is his chance to bury that tag. All that stands in his way is a gifted, young coach strongly influenced by Johan Cruyff who, like Hiddink, learned much of his craft as a coach from Rinus Michels.
Who will tinker?
The other semi-final should be a clash of 4-4-2s, if Sir Alex Ferguson and Arsene Wenger donÃ¢ÂÂt tinker.
ArsenalÃ¢ÂÂs one up front against Chelsea in the FA Cup semi-final looked limp. The 4-5-1 Arsenal played away in their 2006 Champions League run worked because, man for man, Wenger had a better team and because the Gunners didnÃ¢ÂÂt face an English team in the knockout stages.
Alan Ã¢ÂÂSmudgerÃ¢ÂÂ Smith has noted one vital difference between the 2008/09 Arsenal and the invincibles of 2003/04.
Gone are technically gifted, physically powerful athletes like Thierry Henry and Patrick Vieira. Wenger has assembled a nimble, pacy, technically gifted team that lacks physical presence.
This has cost them in the Premier League and may hurt them against United. Some Arsenal fans have, only half-humourously, urged Wenger to buy some players with bones.
A 4-4-2 would make sense. The tie could give Nicklas Bendtner the chance to become more than a legend in his own mind. (Bendtner has actually scored 12 goals this season without significantly endearing himself to Arsenal fans.)
And, as porous as the GunnersÃ¢ÂÂ defence can be, Aalborg and Porto scored twice at Old Trafford.
Arsenal vs United, Wenger vs Ferguson is a perplexing double rivalry that has inspired the Gunners to astonishing heights or led them to the kind of shambling incompetence hitherto reserved for certain Elvis Presley movies of the mid-1960s.
Nobody knows which Arsenal will turn up at Old Trafford. Or which United Ã¢ÂÂ the one that played the first half against Spurs? Or the second?
With five Premier League games left, UnitedÃ¢ÂÂs unsettled defence have already conceded one goal more in the league than 2007/08. And there was nothing especially subtle about the attacking play that put Spurs 2-0 up at half-time.
United stuttered with one up-front in the first half at home against Porto so Ferguson may prefer a 4-4-2 or a 4-4-1-1, perhaps encouraging Cristiano Ronaldo, who led the line superbly in Porto, to play ahead of Berbatov or Rooney.
With a richly talented foursome of Berbatov, Ronaldo, Rooney and Tevez (who will surely feature as an impact sub) Ferguson may see the chance to settle the tie this week.
LetÃ¢ÂÂs hope that one semi is decided by a goal as sublime as Thierry HenryÃ¢ÂÂs against Sevilla.
"Someone order a goal?"
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