The interim manager confirmed he would quit at the end of the season as he criticised the club's owner and supporters following his side's 2-0 victory at the Riverside to set up a sixth round clash with Manchester United.
Chelsea find FA Cup win over Middlesbrough overshadowed by Rafael Benitez tirade
Benitez used the post-match press conference after his side's FA Cup win over Middlesbrough to fire a broadside at the club and his detractors among the support which overshadowed the 2-0 triumph.
After a troubled week that saw Chelsea lose at Manchester City, then media reports of a dispute between Benitez and John Terry, he made clear that his appointment to the club would be short-lived.
"The problem is a group of people who think they can say what they want instead of supporting the team," he said, in reference to supporters who had abused him again at the Riverside.
"They have to support the team, they have to support the players and don't waste any other things because they don't need to be worried about me.
"I will leave at the end of the season, so why do they have to be worried?
"I will do my job, I will try to win every game until the last minute, that's it."
Benitez's astonishing outburst came barely 24 hours after he moved to play down reports of a training ground row with Terry.
In a move which is unlikely to go down well with owner Roman Abramovich, he accused the club of undermining him by giving him his "interim" title when he replaced Roberto Di Matteo, the man who brought the Champions League trophy back to Stamford Bridge last season, in November.
Asked if he had known that would be the case when he accepted the job, Benitez said: "Everybody is interim because after you, there is another one. But in this case, they didn't have anyone, so why put 'interim'?
"It's just to say to everyone, 'Because he was in Liverpool and just in case, we will put interim and then we will wash our hands'.
"Why do you need to do that? The manager is the manager - one month, three months, seven months, he's the manager.
"The reason why a group of fans is not happy is because I was Liverpool manager and we played in the Champions League, massive games. That's it.
"But you can't change that. They were really good, we were really good, it was a confrontation at that stage.
"I am the manager, I am professional and I want to clarify: I will do my best until the last minute, but if they carry on with this agenda, they are damaging the club, they are damaging the team and next year, if we cannot achieve the top four, they have to take a little bit of responsibility."
Asked further if he believed giving him the interim title was a mistake from the start, he replied: "Yes, 100%."
Benitez's tirade completely overshadowed the game, which his much-changed side, led by Terry, eventually won after a difficult first half.
Middlesbrough put Chelsea under pressure, with Rhys Williams probing from midfield and Scott McDonald heading wide half way into the first period.
Muzzy Carayol dragged an ambitious 36th-minute effort well wide, but he forced Cech into a less than convincing save with five minutes of the half remaining when his shot reared up off the turf and hit the keeper in the chest before being bundled to safety.
It took Chelsea 51 minutes to force their way in front when Yossi Benayoun recycled Oscar's cross to Ramires, who curled the ball towards the top corner, clipping Fernando Torres on its way in.
The visitors made sure of victory 15 minutes from time when substitute Eden Hazard laid off the second for Victor Moses, who capped an impressive individual display by tapping home.
Tony Mowbray, the Middlesbrough manager, will look to take some of the positives into the remainder of their Championship campaign, which continues against leaders Cardiff at the weekend.
Mowbray said: "We have got 12 games left now. For six months of this season, we have been in the top six and we have been threatening the top two for most of that time.
"We have obviously fallen off the pace in the last six weeks, for whatever reason, be that injury or the fact we have been involved in cup competitions.
"But we have to get back to business now. We have to start winning football matches again now and our only concern this year is to try to get out of this league."
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