MANCHESTER -- Manchester City manager Manuel Pellegrini revealed that Sergio Aguero had needed treatment on a hamstring injury at half-time as he recorded the quickest ever five-goal tally in Premier League history.

Aguero struck five times in 20 minutes as City, who had been 1-0 down, recovered to beat Newcastle 6-1 at the Etihad Stadium.

Pellegrini substituted Aguero with 25 minutes remaining, which cost him the chance to become the first man to score six goals in a game in the division, but said it had been a precautionary decision.

He told a news conference: "Maybe he can score one or two more, but we have to have a precaution because he can be injured.

"He needed treatment at half-time. He has a kick in his hamstring so it was important just to relax him because he was not 100 percent comfortable."

Pellegrini praised his centre-forward, adding: "It is always amazing to see a player score five goals.

"I am very happy for Kun. He deserves it. He is always a player who makes a difference. For different reasons in the last games, he missed important chances but he was calm.

"He demonstrates every year what he can do. Last year he was the top scorer of the Premier League. Three years ago, he decides the title in two minutes."