Interim Chelsea manager Rafael Benitez will leave the club at the end of the season, the angry Spaniard told a news conference after an FA Cup fifth round win at Middlesbrough.
Benitez was appointed on a short-term deal in November to replace sacked Champions League-winning boss Roberto Di Matteo but was never popular with fans and results have not improved.
"I am a professional and I will do my job. At the end of the season I will leave," he said.
"I'm disappointed with some fans. They have to support the team instead of wasting time making banners.
"They have to support the team. They gave me the title of interim manager which is a massive mistake. I am the manager and I will manage this club. The fans are not helping us."
Second-half goals from Ramires and Victor Moses secured FA Cup holders Chelsea a 2-0 win at second tier Middlesbrough, setting up a mouthwatering quarter-final at Manchester United.
Chelsea, taken to a replay by third tier Brentford in the previous round, improved after a scrappy first half but got a stroke of luck on 51 minutes when Brazilian Ramires let fly from 20 metres and his well-struck shot took a large deflection.
The Premier League side made the game safe 17 minutes from time after fine work from substitute Eden Hazard.
The Belgian exploited a tiring Middlesbrough defence with a strong run down the left, played a one-two with Oscar before squaring for Moses to double the lead.
Benitez made eight changes from the side beaten 2-0 by Manchester City on Sunday, a defeat followed two days later by the Spaniard denying media reports that he was involved in a training ground row with his squad, and in particular with captain John Terry.
Terry, rested for the City defeat and left on the sidelines for several recent games, was restored to central defence against the Championship promotion hopefuls, while Yossi Benayoun and Paulo Ferreira were handed rare starts.
Chelsea were rarely troubled by Boro, although Terry was forced to make one timely clearance late in the opening half when Petr Cech made a hash of saving Mustapha Carayol's dipping shot.
Premier League leaders United will host Chelsea on Sunday March 10. Everton play Wigan Athletic in another top-flight clash at Goodison Park in the first quarter-final a day earlier, followed by 2011 winners Manchester City at home to second tier Barnsley.
A Championship (second division) side is guaranteed a semi-final berth with Millwall welcoming Blackburn Rovers to the capital on Sunday
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