MANCHESTER -- Manuel Pellegrini has said he believes Sergio Aguero can become the best striker in the world and urged Manchester City's top scorer to get even better.
The Argentine has struck in each of City's last five games, including a four-goal haul against Tottenham that saw him displace Carlos Tevez as their most prolific player in Premier League history.
Aguero is also the joint top scorer in the Premier League, along with Chelsea's nine-goal forward Diego Costa, and coach Pellegrini thinks his centre-forward can become the outstanding marksman in world football.
He told a news conference ahead of Saturday's trip to West Ham: "I think he has all the conditions to do that. Sergio is a young player. He has a lot of years to improve, three or four years more than other players [in the City squad]. It just depends on what he wants to do in the future. I think he can get even better."
Aguero also had a purple patch last season, when he scored 25 goals in 23 games, and struck 30 times during his debut campaign at City.
And Pellegrini does not think he has yet reached a new level in the current campaign, explaining: "I don't think it is the best I have seen from Sergio.
"I have known him for a lot of years, before we were here in England, and especially in the season 2011-12, when Manchester City won the title, he was a very important player.
"Last year he was also very important, especially in the first part of the year when he was not injured. After that it was difficult for him, but I was always sure he would return to his normal performance."
Even though Aguero scored, City lost a 2-0 lead in the Champions League on Tuesday when they drew 2-2 with CSKA Moscow in Russia.
But Pellegrini believes they could afford to drop points in Europe more than in England, adding: "In the Champions League, the most important thing is to qualify for the next stage so you can make the mistake. Where we cannot lose points is in the Premier League."
City have yet to win in the Champions League this season, and Pellegrini believes their campaign will come down to the final group game against Roma at the Stadio Olimpico in December.
He said: "I think we have nine points more to play and the game that will decide if we qualify for the next stage will be the game we have to play in Rome."
CSKA were supposed to have a stadium closure as part of a UEFA punishment, but an estimated 300 supporters were present at the Khimki Arena while City had no fans.
While Pellegrini argued that was unfair, he said it was not the reason for the scoreline, saying: "I don't want to have a link the both things, the result and what happened with the fans.
"I think the only punishment was [for] our fans because they couldn't go. For me, it is more important to talk about football, not to talk about rules or punishment."