Manchester City were ruthless, fell asleep and then woke to end a Leicester resistance that came in a sparkling second-half riposte to the champions, who were 4-0 up at the break. But what Pep Guardiola characterised as a “typical Boxing Day” encounter – a throwback to yesteryear’s high-scoring affairs – might have ended differently if Brendan Rodgers’ men were as merciless as City. When James Maddison slipped in Kelechi Iheanacho on 70 minutes, the striker was stopped by Ederson from moving the visitors to only 5-4 behind. Marc Albrighton later spurned a headed chance to do the same. If either opening had been taken, there is no knowing what the closing phase might have thrown up. Guardiola spoke of how even at the interval he did not feel at ease. “The game was open at 4-0, it was not closed,” he said. Yet the bottom line is City have 17 goals in their past three games and remain leaders after completing half their 38 Premier League matches, the victors in all of their last nine. As Guardiola said: “The important thing is that we finish the [first] leg with 47 points. It’s a lot, so we start again against Brentford in three days.” The manager left Phil Foden and Jack Grealish on the bench again, as he plotted to continue a winning run against opponents who had Jamie Vardy among their substitutes due to a tight hamstring. This made the visitors’ challenge even tougher as Vardy’s pace could snare City on the counter, exposing the hardly jet-heeled Rúben Dias and Aymeric Laporte. The problem is City’s ascendancy is predicated on their hogging of the ball. Any defensive weaknesses are nullified if the opposition cannot get hold of it. An illustration came five minutes in. Fernandinho’s chip found Kevin De Bruyne, Bernardo Silva’s run along the blindside dragged out the defenders and the Belgian’s pirouette inside was followed by a cannon of a strike that gave Kasper Schmeichel zero chance. The visitors had been overrun from the opening whistle. Further disaster arrived when Riyad Mahrez swung in a corner and Youri Tielemans grappled with Dias. VAR called Chris Kavanagh to the monitor and, as usual when this occurs, he pointed to the spot. Riyaz Mahrez blasted the kick beyond Schmeichel. With City 2-0 up inside a quarter of an hour there was a temptation to deem this contest over but the response was instant, Maddison forcing Ederson to tip a 20-yard free-kick on to the bar. The goalkeeper then palmed away the corner and saved a low Ayoze Pérez shot. This, though, was the falsest of dawns. Silva, City’s performer of the season, collected the ball and found De Bruyne. The midfielder is the master of the quick tap-on and he fed João Cancelo this way, the right-back crossed, a flailing Schmeichel pushed the ball into Ilkay Gündogan’s path, and he did not miss. Leicester’s shock became embarrassment when City scored a fourth. Raheem Sterling ran at Tielemans inside the area, the hapless No 8 fouled him to give the home side a second spot-kick. This time, despite Guardiola billing Mahrez as City’s best penalty executioner, it was Sterling who beat Schmeichel. City had scored 15 goals without reply in their previous two games plus the first 25 minutes of this one. For the resurgent Sterling it was a seventh in his last nine club appearances. Soon there was nearly a sublime eighth. Oleksandr Zinchenko’s left-footed dink was an exhibition-like pass, the ball floating in on a bewitching parabola to Silva, whose volleyed delivery across goal was equally good, and there was Sterling to take aim, but Schmeichel parried. City closed the half as they began: at Leicester’s jugular, De Bruyne’s free-kick wrong-footing Leicester, setting up a Gündogan rocket that Schmeichel beat away. Rodgers may have missed a whole first-choice rearguard because of injury but the supposed master tactician was still culpable for a passive performance from his side. However, this changed on 55 minutes as a quick break finally unlocked City. It began at the back. Albrighton pinged the ball to Maddison before, really, Dias should have cleaned the playmaker out. The reason he did not, according to Guardiola, is because “one yellow and he is suspended”. Possession went to Iheanacho, who returned it, and Maddison slid in Leicester’s first goal, under Ederson’s body. Seconds later came a near replica. Maddison pickpocketed Gündogan, left Zinchenko and Fernandinho challenging air and rolled the ball to Iheanacho, whose assist this time was for Ademola Lookman. At 4-2 this had become a thriller with fresh life. City had done what Guardiola detests: surrendered the ball. Fernandinho’s riposte was to head what looked likely to be a fifth City goal until Daniel Amartey intervened. In the next twist Iheanacho scored, the striker following up when Maddison’s shot was steered on to the bar by Ederson. Laporte quickly struck back, rising above Iheanacho and Luke Thomas to meet Mahrez’s corner perfectly and stretch City’s lead again. Lastly, after the Iheanacho and Albrighton misses, Sterling made it 6-3. Rodgers offered injury updates on some of his absent players. “Patson [Daka] is probably going to be about three weeks, Caglar Soyuncu about three weeks,” the Leicester manager said, before turning his attention to Ricardo Pereira, who was forced off in the Carabao Cup tie at Liverpool by a challenge for which Tyler Morton was shown only a yellow card. “Six to eight weeks. He has got a fractured fibula – he is lucky it is not worse, how the referee didn’t see that challenge. And then Ryan [Bertrand, a substitute] twisted his knee in the warm-up as well.”