From the moment Daniel Lafferty sent Harry Maguire sprawling, Leicester City knew this was not going to be a routine assignment.
Seconds earlier, the former Sheffield United defender had received a standing ovation from the crowd as they celebrated his homecoming. Less than a minute later, one of the Steelphalt Academy's most gifted graduates was left writhing in pain after being dumped, unceremoniously, on the seat of his pants.
It was a signal, despite making no attempt to disguise the fact the Carabao Cup was not their primary objective this term, Chris Wilder's side were still up for a fight. Indeed, although Craig Shakespeare's men ended the match comfortable victors, United were the dominant force for long periods of this second round tie.
Ultimately, however, it was City's superior finishing, not attitude, which settled last night's match.
Demarai Gray, whose future at the King Power Stadium is shrouded in doubt, broke the deadlock by sweeping home at the start of the second-half before Islam Slimani, the Algeria centre-forward, completed a clinical brace.
Caolan Lavery ensured United's efforts did not go entirely without reward with a fortutious goal during the closing stages but, try as they might, Wilder's charges could not engineer the breakthrough which would have put the outcome in doubt. Ahmed Musa ended all hopes of a comeback by scrambling home at the death.
Bramall Lane has been a graveyard for top-flight teams in knockout competition with United, who reached the semi-finals of the tournament three seasons ago, counting Southampton, Liverpool and Leeds among their prized list of scalps.
Although there was to be no fairytale this time around, the evening was not without merit for the South Yorkshire club and its staff. David Brooks made his presence felt with a series of incisive runs while Jake Eastwood approached his work with maturity and confidence.
Despite using his programme notes to state the importance of momentum, Wilder's priority remains establishing United at Championship level following six seasons in League One. With that in mind, and Saturday's visit of Derby County looming large on the horizon, he dismantled the squad which beat Barnsley last weekend. Brooks, Eastwood and Lavery were among those recalled while George Baldock made his United debut. But it was Ched Evans' presence in the United line-up which sent a ripple of excitement through the crowd before kick-off. The Wales international, starting a match for the first time since returning to South Yorkshire during the close season, fought, foraged and frustrated opponents as United looked to establish a foothold in the game.
But it was Samir Carruthers who became the first of Wilder's players to test Ben Hamer's handling with a rasping long-range drive. Evans positioned himself well underneath an aerial ball soon after only for his header to fall straight into the former Charlton Athletic goalkeeper's palms. Nevertheless, despite failing to make the most of those openings, they served to convince the hosts there was something to be had from the game.
That remained the case right until the 62nd minute when Slimani, following Gray's opener, doubled City's lead.
Eastwood, who like Maguire progressed through United's youth system, showcased his talents with a superb flying save to prevent the England under-21 from claiming another soon after.
Instead, that privilege fell to Slimani who turned home from point blank range after escaping the attention of United's defence.
The scoreline did little to reflect their contribution during an entertaining fixture. But, when United reflect upon their performance, it underlined the importance of a cutting edge.
Slimani pounced againin the 67th minute before Lavery, despite shaping to cross, swept the ball beyond Hamer from outside the box. Substitute Billy Sharp saw a late attempt blocked before Musa's intervention but there was to be no grandstand finish.
Unlike Wilder, whose selections were influenced by concerns about the depth of options at his disposal, Shakespeare's changes were largely through choice. Resting the likes of Marc Albrighton and Jamie Vardy represented a calculated gamble on the 53-year-old's part although, aware of United's giant-killing record, he did keep them in reserve just in case.
When Ahmed Musa, a £16m signing from CSKA Moscow marked his first start since February by miscuing the ball into touch, Shakespeare could have been forgiven for regretting his decision. Maguire followed suit with a rare wayward pass soon after before Musa provided further evidence of the declining correlation between transfer fees and ability by slicing a half chance woefully wide.
Carruthers and Evans both went close before Brooks, midway through the opening period, nearly edged United in front. Ghosting across the box after drifting past his marker, the youngster unleashed a vicious drive which Hamer nearly spilled into the net before recovering at the last moment.
Lavery went close immediately after the interval before Gray helped City wrestle back the momentum with an angled 52nd minute shot which flew past Eastwood and into the back of the net.
Slimani netted twice in quick succession as Shakespeare's men finally moved through the gears before Lavery reduced the deficit. Musa's late strike simply twisted the knife.
Sheffield United: Eastwood, O'Connell, Wright (Basham 68), Lafferty, Freeman, Baldock (Coutts 68), Lundstram, Carruthers, Brooks, Lavery, Evans (Sharp 61). Not used: Stevens, Thomas, Sharp, Coutts, Duffy, Blackman.
Leicester City: Hamer, Chilwell, Gray, King, Musa, Maguire (Knight 80), Amartey, Slimani, Ulloa, Ndidi (Mendy 76), Fuchs. Not used: Vardy, Albrighton, Jakupovic, Okazaki, Mahrez.
Referee: Tony Harrington (Cleveland).
Star Man: David Brooks