Guus Hiddink has firmly ruled out continuing to combine the Chelsea and Russia jobs next season.
Hiddink is set to quit his interim position with the Blues after the FA Cup final on May 30 with Carlo Ancelotti favourite to succeed him on a permanent basis.
"We have done it the past four months because there were only two games in March in the international calendar," said Hiddink. "In June we have another game coming up and the English league is ended. In September, October and November there is a very busy international schedule and when you are in a very big club like Chelsea it is irresponsible to do both jobs."
He added: "It cannot be done. Chelsea are a big responsibility and you have to be in charge, day in and day out."
Hiddink names a Chelsea side in the Barclays Premier League for the last time when they take on Sunderland at the Stadium of Light on Sunday.
A Chelsea victory, combined with other results, could help send relegation-haunted Sunderland down to the Championship.
Hiddink will not field a weakened team, although one or two of his experienced players may be rested against the Black Cats.
But the Dutchman also believes Manchester United will not field a reserve side against Hull because champions always want to win.
"We like to put out a strong team and so do Manchester United," said Hiddink. "I don't know why the league could not be played on a Saturday so United would have an extra day of recovery for the Champions League (final, on Wednesday). If you are a champion, you hate to lose. A good team hates to lose.
"I have not seen many of Sunderland's players but I've been backed up and helped by my backroom staff. Ray Wilkins knows a lot about the English league and Europe as well. He focused with me on the English teams which he did perfectly. I watch rather a lot of DVDs of domestic teams."
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