Four years ago Riyad Mahrez may have been excused mixed feelings when, at the end of his first season with Manchester City, they won the domestic treble. He had hardly been incidental to the fact but nor had he proved pivotal: form-wise it had been a mixed introduction to the relentless demands of Pep Guardiola’s football and he would admit, in hindsight, that settling in took time. You hardly needed to scour the internet’s darkest corners to find references to a £60m flop but his only crime was not being the finished article. Now City are on course for a more glittering triple haul and this otherwise humdrum dismissal of a willing but drab Sheffield United was a reminder of how integral Mahrez has become to what City produce now. He has plugged in to a degree most outsiders failed to foresee; at 32 the flightier edges have been curbed while the gliding, floating guile that made him such a unique proposition in the first place has remained. If three proves the magic number for City come the campaign’s end, Mahrez entered into the spirit here. His hat-trick gave a low-key occasion something to hang on; the solo effort that settled matters offered a moment of genuine excellence by which to mark it. In 85 appearances in the past two seasons he has delivered 39 goals; Guardiola dropped Mahrez during the autumn, unimpressed by a slow start to 2022-23, but he has delivered some of his best figures this term. There had been a subdued feel to the buildup here and it never quite lifted. Wembley was not full and nor did the air crackle with the expectation of a spectacle for the ages. Plenty about this once-feted stage of the cup has been devalued, the insistence on hauling everybody to the national stadium playing no small part. The all-engulfing presence of the Premier League was another diminishing factor. Once a jewel of the season’s business end, this fixture could hardly claim to take priority in either side’s intray even if nobody would sniff at its potential rewards. For Paul Heckingbottom’s side there was the knowledge that their next three points in the second tier, a prize on offer when they host West Brom on Wednesday, will confirm their return to the top. “Promotion from the Championship is the biggest item on our agenda,” Heckingbottom admitted in his programme notes. The likelihood of a thumping from City may have clarified that thinking. But from the early moments it became clear City were not going to cut loose quickly. Anyone expecting a goalfest was instead treated to more of a distraction derby: City’s own pivotal assignment four days down the track has come to look even more tantalising after Arsenal’s draw with Southampton and they operated as if mindful of exactly that. Not that Guardiola took the occasion lightly. While Ederson, Rodri and Kevin De Bruyne were among those benched this was still an A-list selection, especially across the front line. Guardiola had said he would need to smell how well conditioned his key men were before picking his team: he had clearly sensed something sufficiently fragrant in the air. When United’s contingent burst into their marvellous paean to the greasy chip butty, to the tune of Annie’s Song, before kick-off there was, at last, some sense of occasion. One of City’s underrated features under Guardiola is their willingness to dine voraciously at the roadside cafe table before thinking about the tasting menu but they were subjected to some early discomfort. Had Iliman Ndiaye beaten Stefan Ortega within two minutes, the afternoon may even have taken a different hue. Until Daniel Jebbison’s clip on Bernardo Silva, with the interval looming, the first half had passed almost imperceptibly. City had taken 23 minutes to generate a moment of real threat, Wes Foderingham saving from Julián Álvarez; their opponents were happy to concede space and niggle, George Baldock’s swipe at Sergio Gómez the kind of attention Guardiola will not have appreciated. Once Mahrez had converted from the spot, any pretence at jousting on equal terms was over. It became the Algerian’s clinic after that, a driving run and cool finish stealing the scene before a swept shot from Jack Grealish’s cutback confirmed the first semi-final hat-trick for 65 years. City, having never been required to run through the gears, were able to rest the right legs in the right places. United’s fans could filter away, beat the Wembley Way rush and leave ditties referencing their imminent ascent in the air. Their sky blue-clad counterparts could look forward to a more needly meeting with Mikel Arteta’s contenders and, perhaps, a Manchester derby when they return here for the final. Nobody had seen much that will be long remembered, but Mahrez had shown once again that his worth is no longer in doubt.