The Manchester City coach has the upper hand over his fellow Italian but Ancelotti is confident and sure Fernando Torres will get that elusive first goal.
Ancelotti needs to outwit friend Mancini to keep Chelsea's hopes alive
Once his partner in the Italian national team, long a friendly rival across the technical area, Chelsea's Carlo Ancelotti reckons that Roberto Mancini owes him one this afternoon.
"I have a very good relationship with him," Ancelotti said before dryly adding: "Not so friendly because he won too many times against me. He has to understand that I am his friend, so sometimes you can leave something to the friend."
Mancini has taken everything from six of their last eight meetings and arrives at Stamford Bridge in by far the more comfortable position. Both ply their trade for billionaire bosses, both have been relegated to bystanders in the Premier League title race, yet only for Ancelotti does that amount to a suspended death sentence.
At Manchester City the priority is to avoid the ill publicity of another change of coach. When their team tumbled out of the Europa League on Thursday night, an exit accelerated by the brainless sending off of a hand-picked Mancini signing, there was no public admonishment from Abu Dhabi for a manager who, realistically, has only the FA Cup to play for. As long as Mancini extracts a top-four finish from the division's most expensive squad he will remain in situ.
For Roman Abramovich, last year's league and FA Cup double has long since been discounted. Chelsea's owner takes every defeat personally, sees a team nine points behind the leaders, out of both domestic cups and more regularly embarrassed than at any point in his turbulent stewardship.
The Russian is, it seems, already preparing Ancelotti's replacement - leaving Champions League success the manager's best hope of survival.
Furnished with the £50 million (Dh298m) emergency acquisition of Fernando Torres, it has not helped Ancelotti's cause that none of his centre forwards have scored in the league since the Spaniard's January deadline-day recruitment.
Four league starts have delivered just one shot on target from a player Abramovich now expects his team to be built around.
Cue the frenzied changing of the formation with which Ancelotti has attempted to accommodate Torres. Five distinct shapes were tried before landing a run of positive results with a system alien to past Ancelotti sides. Not long after his arrival at Chelsea, the elder Italian explained that he would never use such a conventional 4-4-2 because "I don't like to play with the wingers".
With no defined holding midfielder and none of his wide men particularly comfortable in their new positions, the system seems to have been retained more to ride the confidence of a rare run of undefeated outings than because Ancelotti considers it a long-term solution.
"I think there was a time when our play was too slow and we had difficulty to create situations," Ancelotti said. "We use it to press the ball quickly so we can use transitions to create more opportunities. It was good against Copenhagen [in the Champions League]. Sometimes we can change our football, but our philosophy is the same, to play with possession. I think defensively we are more compact with 4-4-2."
Ancelotti's stance on Torres is that he does not care whether the striker scores or not as long as he works hard and the team does. It has not endeared him to Didier Drogba, who, with more shots on target than any other Premier League player and more assists than every striker bar Wayne Rooney, wants out of Stamford Bridge.
"I don't have a first-choice attack. I want to rotate the front players because they are in good condition and are motivated," Ancelotti said before quipping: "And they don't score, so there's no difference.
"It depends on which tactic we want to use. Obviously, if we want to use quick transition and counter-attack then we can use [Nicolas] Anelka because he is quick. If we want power we have to use Drogba."
Mancini has to deal with Mario Balotelli's disruptive behaviour; Ancelotti is at least working with an adult. Torres had remained calm and co-operative, worried more about the impact on the club of his failure to find the net than on himself.
"There is no pressure whatsoever," Torres said. "People make me feel welcome again and as long as the team is winning things are going to be easier. That is what matters. A month ago it looked like we couldn't fight for a position at the top of the table. In three matches things change, Manchester [United] lost and now we are closer to the top [and] in the quarter-finals of the Champions League. The best part starts now. I'm adjusting to being here and happy."
Torres will start against City aware that a rare victory over them will propel his team above a direct rival for Champions League qualification. He said today's game "is vital because if we win we can take third place with a game in hand over them which would be a big boost for the team and our confidence levels. And third would be closer to Manchester United, closer to Arsenal".
And that problematic first goal? "It's coming soon. Sunday."
David Luiz v Carlos Tevez
Luiz’s presence in Chelsea’s defence will help them cope with the counter-attacking style of their opponents. However, Luiz, below, is prone to giving away silly fouls and Tevez is very adept at getting into dangerous positions and tempting defenders into making rash challenges.
Carlo Ancelotti will be expecting his misfiring strikers to rediscover their scoring touch, with Fernando Torres yet to open his account. Roberto Mancini, the City manager, will look to his players to exploit any gaps left at the back with quick counter-attacks.
City are unbeaten in their last eight visits to Stamford Bridge and Chelsea have only won their three times in the last seven matches. However, victory over Manchester United two weeks ago has boosted hopes that the hosts are recovering their form for a late title push.
Chelsea (4-4-2) Cech; Ivanovic, Luiz, Terry, Cole; Ramires, Essien, Lampard, Malouda; Torres, Drogba
Manchester City (4-3-1-2) Hart; Richards, Kompany, Lescott, Kolarov; Y Toure, De Jong, Barry; Silva; Tevez, Dzeko
• When City defeated Chelsea 4-2 last season it ended their 37-match unbeaten run
• Before the 2009/10 season, City had only won two of 24 league matches against Chelsea
• City have not won away from home in the last eight games in all competitions