Chelsea interim manager Guus Hiddink said he was "delighted" with his players after they cruised into the FA Cup fifth round -- and a home tie against Manchester City -- with a 5-1 win at Championship side Milton Keynes Dons.
Oscar scored a first-half hat trick and Eden Hazard struck from the spot before Bertrand Traore rounded things off with a fifth.
The hosts levelled against the run of play when Darren Potter's deflected shot flew in, but it proved only a brief setback for a Chelsea side rediscovering their form.
Hiddink told the BBC: "We are delighted. The concentration against the big teams is always high, but in these games you have to be well prepared mentally. They got even, but we reacted very well.
"What I asked in the beginning [of his interim spell] was what was the contribution they made to be champions last year? I wanted the contribution they did then.
"I asked the players: 'what did you do? Let's try to go back to what your basic skills are.'"
Hazard's penalty ended a 31-game goal drought, with the Belgium international taking it after captain John Terry appeared to intervene to make sure that he did.
Hiddink said: "They decided themselves because we have this hierarchy of the penalties. Oscar gave it to Eden, as everyone knows he has not scored for a long time."
And he praised Oscar for his contribution, saying: "Oscar is playing with a smile on his face, and that's what I like with the players."