Man City manager Pep Guardiola highlights Sheffield United's "excellent" work

Manchester City manager Pep Guardiola (right) and Sheffield United manager Paul Heckingbottom: John Walton/PA Wire.

Highlighting an early chance for Iliman Ndiaye and Riyad Mahrez’s converted penalty on the stroke of half-time as pivotal moments of the contest, Guardiola acknowledged United had caused his treble-chasing squad a number of headaches before two more strikes from the Algerian settled the tie.

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“The penalty, that was very important of course and these moments (Ndiaye’s opportunity) are key,” Guardiola said. “They defended very well and we started to play anxiously, so they are in the game. That means these moments that we have just spoken about, they are so important.”

Sheffield United manager Paul Heckingbottom applauds the fans after the Emirates FA Cup semi final match at Wembley: John Walton/PA Wire.

“They are excellent from set-pieces,” Guardiola said. “Very, very good.”

Despite travelling to London as huge underdogs by virtue of their Championship status, United could have taken the lead almost straight from kick-off when an Oliver Norwood corner was met by John Egan who diverted the ball into Ndiaye’s path. As Heckingbottom held his breath on the touchline, the Senegal international attempted to thread the ball past Stefan Ortega but the German scrambled it away.

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With the match still deadlocked as the interval approached, Bernardo Silva was fouled in the area by teenage centre-forward Daniel Jebbison and Mahrez claimed the first of his three efforts from the spot. Heckingbottom later insisted there had been “just as much contact” when United substitute Chris Basham was clipped by Aymeric Laporte during the closing stages, and referee Stuart Attwell waved play on. But he conceded he “thought the decision was correct” at the time, also going on to express his frustration at the defensive lapse which presented Mahrez with his second after the break.

Manchester City manager Pep Guardiola speaks with Manchester City's Sergio Gomez: Nick Potts/PA Wire.

With United needing only three more points to seal automatic promotion from their remaining four league outings, Guardiola said: “Effectively, Sheffield United are already a team that is in the Premier League next season, so that means we know they are very good. They didn’t allow us to press with the longer balls, and they fought.”