Derby County got back to winning ways with a hard-earned victory over high-flying Sheffield United on Saturday evening.
The Rams got in front after 20 seconds to set the tone for the remainder of a largely pulsating game, and despite United levelling before half-time and looking a threat throughout, Jack Marriott's fine winner meant the points went to the hosts.
It was arguably Derby's biggest test so far in a week where they will next travel to face two other sides at the top of the table, but this will set them off on those respective journeys in high spirits as they more than matched the visitors in every department.
United will undoubtedly remain in the upper echelons of the league but will rue not testing the Rams defence more than they did despite some promising attacks - Derby protecting their goal well and looking dynamic going forward with Marriott always a useful outlet. Richard Keogh was outstanding throughout at the back.
And it all means Derby return to the top five where they'll be aiming to remain by the end of their testing run of games ahead.
The game couldn't have got off to a better start for the hosts. Having kicked off, they attacked right away and after Harry Wilson had crossed and Marriott laid the ball back, Craig Bryson placed his shot into the corner of the net and the Blades were behind before they'd even touched the ball.
Things then settled a little as the game remained open but with few chances, Enda Stevens seeing a shot blocked in the penalty area after 26 with the first effort of note since the goal although both sides were attacking with good intent, the Rams mostly on the counter.
Stevens drilled a low shot straight at Scott Carson on 32 minutes as United aimed to get level, something they finally achieved on 41 minutes and it wasn't undeserved. John Fleck was the architect with a great run into the penalty area and then to the byline, which arguably should have been stopped by the Rams defence, from where his cross found centre-back Chris Basham who was at the back post to slam home from close range.
Martyn Waghorn then headed a good chance wide from Craig Forsyth's left wing cross when he should have at least hit the target, before Marriott's shot was well blocked by Dean Henderson and from the ensuing break, Mark Duffy shot wide across the face of Carson's goal as the half then ended.
The second period continued in a similar vein, Derby close to levelling on 53 as Tom Lawrence, who had replaced the injured Bryson late in the first-half, was sent towards goal by Jayden Bogle's fine through ball but his shot was deflected over by John Egan.
Waghorn then came very close with an effort from just outside the box which narrowly missed the angle of post and crossbar. Lawrence then driving forward before shooting just wide not long after the hour mark.
The second Rams goal finally came on 77 minutes and it was a superb finish from Marriott, who got in front of his man to meet Forsyth's cross and guide the ball past Henderson and into the net.
Derby had a let off as Carson then dropped a right-wing corner with eight minutes to go, two defenders managing to save him by getting the ball off the line, Carson then pushing David McGoldrick's low shot wide seconds later to atone for his error.
But that would be all United would have left to throw at the Rams, who held on to claim an impressive three points.
Derby: Carson, Forsyth, Bryson (Lawrence 36), Tomori, Keogh (c), Wilson, Mount, Waghorn (Jozefzoon 71), Marriott (Davies 86), Bogle, Huddlestone.
Subs not used: Roos, Johnson, Nugent, Malone
Sheffield United: Henderson, Stevens, Fleck, O'Connell, Basham (Washington 80), Sharp (c) (Clarke 65), Egan, Norwood, McGoldrick, Freeman, Duffy (Coutts 65)
Subs not used: Moore, Stearman, Johnson, Cranie
Ref: Oliver Langford