Aguero needs just one more goal to equal the club’s all-time scoring record of 177 goals currently held by Eric Brook.

Walker is not surprised that the Argentine ace now finds himself on the brink of matching a record which has stood for 78 years.

The England star, who joined City in a £54m deal from Tottenham this summer, admits Aguero was a total nightmare to face when he used to be on the opposite side.

Now he is relishing helping Aguero continue his goal run tonight in the Champions League against Shakhtar Donetsk rather than trying to stop him.

“To play against him is an absolute nightmare,” said Walker.

“I’ve faced him numerous times down the seasons and he always seemed to score against us.

“It was frustrating. Having him on the same team now is a bonus because he is such a quality player.

“You see what he has done in the Premier League. Around the dressing room, he can help the younger lads.

“If things aren’t going well, he is the kind of player who can produce that bit of magic you need.”

Walker has revealed Aguero is like a silent assassin both on and off the pitch and has an aura about him that makes colleagues raise their own standards.

He said: “On the field, there is no difference.

“Off the field, he is a bit quieter than I thought, but his presence around the place gives off the vibe of winning.

“He has a winning mentality and he wants the best. Anything below par and he will be one of the first to say ‘come on, this isn’t right’.”

City have made an unbeaten start to the season and go into their home clash with Shakhtar high on confidence following six straight wins.

That run has seen them score a remarkable 24 goals, including a 4-0 win at Feyenoord a fortnight ago.

And Walker reckons few teams will stand a chance of stopping City if they continue to maintain the same standards.

“It is a good dressing room to be around,” he said.

“We need to keep working hard and doing what the gaffer says, keep attacking and offering that outlet.

“It is just about consistency, because if we keep playing at the level we are playing at we won’t come up against many opposition who will cause us problems.

“With the strike force we have got and keep keeping clean sheets, we will be hard to stop.”