While the quality of the opposition has to be taken into account, there was no disguising Chelsea's desire to make a statement, nor their capacity to do so. The victory brought them within five points of leaders Arsenal, with a game in hand and the Gunners due at the Bridge in 10 days' time. A season mired in controversy may yet end in triumph. "What happened on Saturday happened," said Grant in reference to the FA Cup exit at Barnsley. "We were not happy but we know we need to continue. So far in the league we have done well and we will fight to the end."
Grant, who was booed by a few Chelsea fans as he took his seat, would be entitled to have left with a broad smile on his face. Of course he did not. Perhaps he was wise. The board will have noted the sub-par attendance; 3,000 below capacity, the lowest league gate of the season.
Those who stayed away missed a commanding performance from Frank Lampard. Badly missed at Oakwell, he helped himself to four goals here. Lampard's contract negotiations remain unresolved but Grant said: "I think he will be here next season. I am almost sure about it."
Joe Cole who, like Salomon Kalou, scored once, was equally responsible for the rout. David Jones' late goal was no consolation.
"It was a world heavyweight champion against a lightweight," said Derby's manager, Paul Jewell. "I spent the night squirming in my seat. They are a great team, and we are not."
Jewell admits he has written this season off. Derby have won once, in September, have collected 10 points from 29 games and are 16 points adrift of safety, well on course to set new Premier League records for least points won and most goals conceded. Chelsea, however, are the "crisis club", with Grant said to be under pressure from a mutinous dressing room and a discontented owner. They are third in the Premier League and in the last eight of the Champions League. How Derby would love a crisis like that.
Chelsea, though, do have to be judged differently because of their spending, even if the brightness of the spotlight owes much to their being based, with the national press, in the capital. The financial aspect colours everything, even their progress to the FA Youth Cup semi-finals, which is mentioned here because it was hailed pre-match last night, perhaps to take minds off the FA Cup. It is a shame many of Chelsea's youth players have been bought in.
The man with the mike could hardly be blamed for trying to lift a flat atmosphere. Chelsea, showing five changes from Saturday as Grant reverted, goalkeeper apart, to the team which had won 4-0 at Upton Park, soon lifted the mood. Lampard, released by Kalou's clever reverse pass in the second minute, rolled a shot past Roy Carroll only to see it strike the post and bounce out.
A massacre loomed yet, two minutes later, Kenny Miller outwitted John Terry to run on to a through-ball. He shot wildly but it was a warning to take nothing for granted. Not that complacency was a problem, Saturday's defeat was too fresh in the mind for that. The issue was nerves, brought on by expectation and fear of a repeat of the Barnsley fiasco.
Derby, though, did not set about Chelsea the way Barnsley had. Instead they retreated into deep defence – perhaps because they were pitting a central defence whose combined age was 69 against the pace of Nicolas Anelka. That tactic was undermined when Alan Stubbs limped off to be replaced by Dean Leacock. There is a reason Leacock has been displaced by the thirtysomethings and his naïvety was revealed 11 minutes later when he dived into a challenge on Lampard as the midfielder ran on to Joe Cole's pass. Lampard slid home the penalty.
Miller then stretched Carlo Cudicini from an Eddie Lewis free-kick but the siege quickly resumed. Under constant pressure a defence which has been changed as often as Derby's is liable to break; so it did. Two minutes before the interval Darren Moore dithered as Anelka chased a Lampard pass and Carroll cleared hastily but only as far as Kalou, who chipped into the empty goal.
Derby moved to 4-4-2 soon after the break but any hope of salvaging a point soon disappeared. Anelka, who troubled Derby all night, linked with Joe Cole whose low cross was tapped in by Lampard. That was the first of four goals in 16 minutes. Joe Cole tapped in after Carroll had denied Anelka. Lampard took a short pass from Kalou, strolled forward and drove in from 25 yards to complete his hat-trick. He then weaved around two defenders before sliding a shot inside the near post. It was Lampard's first four-goal haul and took his tally to 17, not bad for a "quiet" season.
Derby's long-suffering supporters were given some relief when Jones scored their first goal for five hours and 44 minutes. Grant then allowed Shevchenko a rare outing and Chelsea (coincidentally) lost their menace. But Derby needed the respite. On Saturday they play Manchester United.
"Did Chelsea look like a club in crisis?" Jewell was asked. "I was too busy looking at our crisis," he replied.
Goals: Lampard (28) 1-0; Kalou (42) 2-0; Lampard (57) 3-0; J Cole (64) 4-0; Lampard (66) 5-0; Lampard (72) 6-0; Jones (73) 6-1.
Chelsea (4-3-3): Cudicini; Ferreira, Carvalho, Terry, A Cole; Makelele (Essien, 73), Ballack (Drogba, 67), Lampard; J Cole (Shevchenko, 74), Anelka, Kalou. Substitutes not used: Hilario (gk), Alex.
Derby County (4-5-1): Carroll; Edworthy, Moore, Stubbs (Leacock, 16), McEveley; Ghaly (Earnshaw, 52), Savage, Pearson, Lewis (Jones, 58), Sterjovski; Miller. Substitutes not used: Price (gk), Villa, Earnshaw.
Booked: Derby McEveley.
Referee: C Foy (Lancashire)
Man of the match: Lampard.
Attendance: 39,447.
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