Any concerns after a 4-0 mauling at Chelsea on the opening day that they would not be able to stand the pace had already been eased by victories against the likes of Watford and Leicester. Here they found confirmation that Derby County, top 10 material for the past two years, must now be ranked among the third of the three different tiers that make up what some still imagine to be the strongest league in the world.
Kevin Phillips, such a prolific goalscorer at the lower level, put to shame anyone who had doubted his genuine ability with a hat-trick that emptied the ground long before the end. The remaining home supporters could not even be bothered to boo, as they had done at half-time with their side 2-0 down.
"People had a right to ask if he'd be good enough at this level, because he'd never played there," Sunderland's manager, Peter Reid, said charitably. "But everyone at this club knew he'd score goals." And so he has, with seven already this season.
Reid, also learning fast, had taken the rotation system to its ultimate in midweek, fielding 11 reserves for the Worthington Cup tie against Walsall (which was won 3-2), then restoring the first team yesterday. They seemed to appreciate the rest.
Derby's Jim Smith, however, must wonder where to turn next. A defence bereft of Igor Stimac, who looks like being an excellent signing for West Ham, could not cope on the ground or in the air; the midfield, despite young Seth Johnson's promise, barely created anything; and the attack had little more to offer than an occasional turn of pace from the Argentine Esteban Fuertes.
Fuertes, presented with possession by Nicky Summerbee early on, had the home side's only sniff of a chance in the first hour. He forced Thomas Soren-sen to fall at his feet and concede a corner, which Paul Butler headed out from under the bar.
Summerbee soon recovered from his error to establish a mastery over the Derby wing-back Stefan Schnoor that delivered a goal after 24 minutes. Having been refused a penalty after an unwise challenge by the German, Summerbee won a free-kick further out on the right, which he hoisted towards Niall Quinn. The home defence were unable to clear and after a messy scrimmage Gavin McCann shot low into the corner of the net. The backline was at fault again just before half-time, allowing Michael Gray to collect a return pass in space from Stefan Schwarz as they waited in vain for an offside decision. Gray's cross gave Phillips a tap-in.
Smith reacted at the interval by withdrawing Schnoor and Mikkel Beck, only to suffer a double blow with two more goals conceded inside 10 minutes. Gray created each of them.
First he launched a diagonal cross that Horacio Carbonari obligingly headed across his own penalty area for Phillips to volley in. Three minutes later, just after Stefano Eranio had pulled up lame, the goalkeeper Russell Hoult misjudged Gray's floated free-kick and Quinn headed over him for the fourth.
One disgruntled home supporter made his feelings known with a foray on to the pitch, which at least guaranteed that he did not have to suffer the sight of Alex Rae opening up the Derby defence again for Phillips to complete his hat-trick.