When he turns in performances like the one that terrorised Championship pacesetters Sheffield United at Bramall Lane this evening, it is hard to believe that Ryan Sessegnon is just seventeen. The teenage starlet celebrated his fiftieth senior appearance for Fulham with a hat-trick that blunted the Blades’ bid climb above Wolves at the top of the table, ended the Whites’ six-game winless streak and earned Slavisa Jokanovic’s side their first win at the oldest league ground in English football since Leroy Rosenior grabbed all three points in April 1985.

The visitors were grateful for Sessegnon’s predatory instincts at the end of 105 pulsating minutes because they were somehow clinging on by their fingertips to a precious victory, having been 5-2 ahead with twelve minutes to go. Chris Wilder has already proven that he doesn’t know how to go gently into the night – and his side were almost rewarded for their commendable never-say-die attitude. Substitute Samir Carruthers cut the gap to just two goals with four minutes to play and, when Leon Clarke powered home a close-range header for his third of the evening in the first of six added minutes, it appeared the home comeback was on.

Somehow a shattered Fulham defence held firm and, with James Linnington waving away penalty appeals at both ends in a nerve-shredding finale, it was left to captain Tom Cairney to carry the ball deep into United territory and earn Jokanovic’s side the most improbable victory of their stuttering season. It owed much to the returning Liverpool loanee Sheyi Oyi, whose early recovery from a dislocated shoulder allowed him to score twice either side of half-time and create another goal for Sessegnon. The England Under-20 World Cup winner more than justified the faith his head coach showed in him – and injected both pace and power into what had previously been a rather toothless Fulham attack.

The evening had initially appeared to be following the traditional script in S2. The Blades began with all the intensity and confidence of a side that has got used to sweeping opponents aside over the past two seasons, although Jokanovic and his coaching staff would have been furious with how former Rangers midfielder John Fleck was encouraged to carry the ball to within 20 yards of the Fulham goal and rifle a shot at David Button. The Fulham goalkeeper did well to get a hand to it, but as the visiting defence stood and watched, Clarke poached his tenth goal of the season. It was inexcusably easy.

Nobody could have legislated for the turnaround that occurred in the space of a couple of minutes just before the half-hour. Ojo had already shown the appetite to get behind the Blades back line and he certainly didn’t need any invitation to gallop onto a woefully underhit backpass from Cameron Carter-Vickers and tuck an assured finish past Jamal Blackman. From their next attack, Fulham went in front. Sessegnon, starting as the left winger in a fluid front three, drove at the heart of the home defence – ignoring the intelligent run of Floyd Ayite outside him – and bent a brilliant finish beyond Blackman’s left hand from more than 20 yards. It was a thing of a beauty from the European U17 champion who turned down the continent’s leading clubs to continue his footballing education at Fulham.

An insanely open contest developed a physical edge to it as the first half wore on with John Lundstram, who came in after Paul Coutts unfortunate leg break at the weekend, lunging nastily at Tom Cairney and Billy Sharp manhandling an incensed Ryan Fredericks. Fulham looked to have weathered a prolonged spell of home pressure, but Clarke slipped past Tim Ream with a stepover to create half a yard of space and his low drive burst through Button at the goalkeeper’s near post to level the scores. It was another tame goal to concede – and Fredericks’ enraged scowl at the ease with which the Blades wiped out Fulham’s advantage said it all.

Jokanovic has always encouraged his side to play with freedom and, incredibly, they went back in front before a breathless first period had even concluded. The excellent Ojo sauntered down the right and carved out an inviting cross, which Sessegnon stroked home on the volley at the back post. Wilder’s men emerged with renewed purpose after the interval and both Jack O’Connell and Clarke went close with chances earlier in the second half before an excellent piece of defending from Ream denied Enda Stevens a sight of goal.

The Blades then threw on the impressive David Brooks and Carruthers in an attempt to conjure up an equaliser but it was actually the Londoners who increased their lead on the break. The recently introduced Aboubakar Kamara accelerated away from the Blades defence and unselfishly squared the ball for Ojo, whose low finish squeezed past Blackman with the aid of a deflection. When Cairney acrobatically cleared James Hanson’s header off the line and Sessegnon completed his hat-trick with a rasping drive from the right angle of the box, Fulham seemed home and dry at 5-2.

But that reckoned without United’s undying spirit. After Kamara had an audacious finish ruled out for a seemingly innocuous challenge in the build-up, the Blades took renewed belief from Carruthers’ deflected strike that completely wrongfooted Button. The streams of home fans who had left early looked to have overlooked their side’s battling qualities when Clarke converted a dangerous cross from his captain Sharp to claim his second hat-trick in successive Bramall Lane appearances – and Fulham were left nervously clinging to the slenderest of leads during a seemingly never-ending period of added time.

SHEFFIELD UNITED (3-5-2): Blackman; Carter-Vickers (Brooks 58), Jake M. Wright, O’Connell; Basham, Stevens, Lundstram, Duffy (Carruthers 60), Fleck; Sharp, Clarke. Subs (not used): Moore, Stearman, Donaldson, Lafferty.

BOOKED: Lundstram, Sharp, Brooks.

GOALS: Clarke (6, 39, 90+1), Carruthers (86).

FULHAM (4-3-3): Button; Fredericks, Odoi, Kalas, Ream; McDonald (Johansen 83), Norwood, Cairney; Ojo (Fonte 74), R. Sessegnon, Ayite (Kamara 68). Subs (not used): Bettinelli, Edun, de la Torre.

BOOKED: Fredericks, Ayite, Odoi, Kamara.

GOALS: Ojo (28, 69), R., Sessegnon (30, 43, 78).

REFEREE: James Linnigton (Isle-of-Wight).