Chelsea & Liverpool under scrutiny
Chelsea and Liverpool's players will also have something in common at Stamford Bridge on Sunday, other than the annual pursuit of Manchester United at the Premier League summit.
John Terry and Steven Gerrard will lead out two sets of players with the angry words of their respective managers still ringing in their ears after an uncomfortable week at home and abroad.
Ancelotti was unhappy with Chelsea's display in Nicosia
Ancelotti's permanently raised left eyebrow hints at a laconic sense of humour, but both were heading skywards in alarm as the Italian lambasted Chelsea for their performance in the Champions League win against Apoel Nicosia in Cyprus.
It came hard on the heels of defeat at Wigan, an appalling display that drew savage criticism and a public dressing down for the players from their leaderTerry.
Benitez meted out similar treatment to Liverpool after a dreadful night in Florence against Fiorentina. Fabio Aurelio, a long-time employee of Benitez both at Valencia and Liverpool, admitted he had never seen him so angry as he was at the interval during the 2-0 defeat.
Benitez rated it right down there with the worst preformances of his Liverpool reign, and was so unsettled by the experience that rage replaced the icy reserve with which he usually treats his charges.
So when Ancelotti and Benitez meet in domestic combat for the first time, both Chelsea and Liverpool will be under intense scrutiny. Weaknesses and strengths will be examined in even finer detail.
Manchester United may currently head the table, but Chelsea and Liverpool have serious designs about unseating Sir Alex Ferguson's champions and Sunday will inevitably used as evidence to either press or dismiss their aspirations.
For Chelsea, there is an echo of last October's meeting with Liverpool when Xabi Alonso's deflected goal ended an unbeaten Premier League run stretching back 86 games.
Then, as now, Chelsea had made an promising start under a new manager. For Ancelotti read Luiz Felipe Scolari, who was winning plaudits for his smooth transition at Stamford Bridge.
How wrong we were. Liverpool's win exposed the fragile foundations of Scolari's regime, falling around a tactical inflexibility that offered Plan A, and when that went wrong some more Plan A. Benitez struck on the notion that if you stopped Chelsea's full-backs attacking under Scolari you stopped Chelsea - he was correct and Liverpool's win was the beginning of the end for the amiable Big Phil.
Ancelotti is prepared to be more experimental and will want to see swift signs that Chelsea have not been unnerved by the dismal defeat at Wigan, and the uncertainties of Cyprus that saw him as uncomfortable as he has been since arriving in England.
The task has been made harder by Petr Cech's suspension, with likely replacement Hilario barely passing muster as a goalkeeper of Premier League quality. Chelsea's miserly defence looked decidedly vulnerable at Wigan and in Cyprus, and even Hilario's greatest admirers would struggle to regard him as a reassuring presence.
Ancelotti must hope Frank Lampard's uncharacteristic drought of eight goalless games does not continue as the usually prolific midfield man adjusts to the coach's diamond midfield formation. Lampard's strength is arriving late in the box - the danger for Liverpool is that he is too astute and too good a player not to fire eventually.
A convincing Chelsea win will cement Ancelotti's reputation and help banish any lingering fears he might turn out to be another Scolari. The Italian's pedigree suggests otherwise, but victory on Sunday will knock out any dents in confidence after a poor week.
Liverpool will take heart from their performances at Chelsea last season, following up that league victory by almost overturning a 3-1 defecit at Stamford Bridge in the Champions League quarter-final.
Fernando Torres is in the mood to terrorise Chelsea, but Liverpool's switch to a more attacking mindset has exposed worrying weaknesses at the back. For those who tipped Liverpool to win the title this season, myself included, there have to be indications of Benitez finding a balance.
Liverpool hope Fernando Torres will be back on top form against Chelsea
The ease with which an unremarkable Fiorentina side threatened to take Liverpool to the cleaners in the first half was undoubtedly the reason for Benitez's burst of anger - but the manager himself has had better nights.
He may have brushed off criticisms of this baffling selection later, but you would not place large sums on it being repeated at Chelsea if Javier Mascherano is still sidelined with a hamstring injury. The dustbin is the best place for that particular piece of tactical thinking.
Liverpool's central defence has not been a happy place to be when the heat is on this season, with Jamie Carragher's dip in form allowing the collapse of Martin Skrtel's game to slip under the radar.
Skrtel threw his hands up in what was almost a gesture of surrender as he was being given the runaround at the Stadio Artemio Franchi. Not great body language, and how Benitez must yearn for the day when Daniel Agger cuts his ties to the treatment room and puts his hand up for selection.
Liverpool have cured the problem of struggling at Anfield against the lesser lights, thrashing Stoke City, Burnley and Hull City, but they have looked ill-at-ease when winning at Bolton Wanderers and West Ham United and slipped against Spurs and Aston Villa.
It will be a serious demonstration of intent if they can win at Chelsea. Didier Drogba, a scourge of Liverpool in the past, was missing when they won at Stamford Bridge last season. He will be present in all his menacing glory on Sunday - and if Carragher and Skrtel defend as they have been when placed under stress then he will be the match-winner.
The same will apply to Torres if Chelsea show the frailty that has marked their last two performances. Two world-class strikers will relish the prospect of feasting on flawed defences.
For the two teams, this game is an early marker for where their league season might be heading. Ancelotti and Benitez only meet when the stakes are high - they do so again on Sunday.
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