Manchester City boss Manuel Pellegrini revealed that Sergio Aguero required hamstring treatment at half-time, before unleashing five finishes that put Newcastle United to the sword at the Etihad Stadium.

Pellegrini said Aguero was still struggling with an injury from the 2-1 midweek win over Borussia Mönchengladbach in the Champions League. But the 27-year-old brushed his injury aside, completing a five-goal domination by the 62nd minute, only fifth player to achieve this in the Premier League era.

"Maybe it was very good treatment," Pellegrini joked at the post-match press conference. "He had a kick in his hamstring so it was important just to relax him a little bit because he was not 100% comfortable."

"We don't know if he could have scored more goals, but we know he had an important kick from Wednesday in Germany," he added.

"He was having some treatment during half-time, so I think to give him more minutes… maybe he can score one or two goals more, but we need to have precaution about his kick because after that he can be injured."

Aguero has struggled to find the form that won him the Golden Boot last season until his exploits against Newcastle. His previous goal from open play came in City's second match of the season against Chelsea.

"I am very happy for Kun because he deserves it," added the Chilean. "He is always the player that makes the difference but for different reasons. In the last game, he missed important chance but he was calm and that was very clever for him to be calm".

"To see him play at the level he plays, it is not just me who must be happy. I think that all the fans [are happy] because really he is a different player. Kun is always calm, but I think he was very, very happy. He is a scoring player and he wants to be the top scoring player – he was not scoring the amount of goals that he normally does. He was very happy and I hope that he will continue in the same way," added Pellegrini.