Manchester City picked up where they left off last season with a routine 3-0 win at Burnley on Friday night – but their victory came at a cost as key man Kevin De Bruyne sustained another injury. Erling Haaland scored two fine first-half goals, but in between those strikes, De Bruyne left the action with what manager Pep Guardiola said was a recurrence of the hamstring problem he suffered in June's Champions League final win over Inter Milan. Rodri blasted home a third from close range midway through the second-half to seal a win that was never in doubt for the defending Premier League champions. But Guardiola said: "[De Bruyne] was injured again, unfortunately. Same place and position as the Champions League and he will be out for a while. "Same issue [as last season] he told me. So that is a problem. We need to go back and reflect with the medical team. "He was feeling really good and playing really good in the first minutes. But unfortunately he is injured again. Maybe [he shouldn't have started], but what happens in the first 15 minutes could also have come in the 50th, 65th, 70th minute..." Newly-promoted Burnley, who romped the Championship under City legend Vincent Kompany last season, tried to rally at times but were largely unable to trouble Ederson in the City goal. Their night got worse in the closing stages as Anass Zaroury was dismissed for a lunge on Kyle Walker. Kompany said: "It's a mentality thing. Today has to be the worst we are ever going to be this season because this team is focused on progress. "I don't know who in my squad will make it to the top level, but I know some of them will. It takes hard work every day, this squad wants to learn and progress together. "That is the mission for us. Results come because you do the work in the background, and we have that here." As if to send out a warning to their rivals, City scored with virtually their first attack of the new season when Rodri nodded down De Bruyne's deep cross and Haaland swept home for the opener after just four minutes. Not to be disheartened, the Clarets came back and enjoyed a rousing 20 minute spell, roared on by the home crowd. They thought their luck might be turning as De Bruyne limped off to be replaced by summer signing Mateo Kovacic. However, with Haaland on the pitch, City always posed a threat and he made it 2-0 on 36 minutes – somewhat against the run of play – as he curled home a sublime strike off the underside of the bar. That understandably knocked the wind out of Burnley who attempted to regroup at the break but were unable to make much of a dent against a City side in cruise control. And the result was put beyond doubt on 76 minutes as a City free-kick from the left unsettled the home defence and Rodri tucked away the loose ball. Burnley's misery was complete in the dying moments when Zaroury was shown a red card – after a VAR review – for a dangerous tackle on Walker.