Despite the high-profile nature of his club-record transfer from Atletico Madrid, the 23-year-old appeared quite at ease in the city which is likely to be his home for the next five years.

Aguero flew in from Buenos Aires, via Heathrow, early in the morning and went straight to a private Manchester hospital to undergo his medical.

He then had a brief stop at City's stadium before deciding lunch was the next most important thing on the agenda and so disappeared for a few hours before returning to the ground in the early evening.

After holding discussions with City officials, the son-in-law of Argentina icon Diego Maradona happily signed autographs for the growing crowd of fans who had gathered to see their new hero.

City have yet to confirm the finalities of the deal, which is expected to be completed tomorrow, but it is anticipated there will be no last-minute hitches.

Just after touching down in the north-west earlier in the day, Aguero wrote on Twitter: "Just arrived in Manchester to finalise the details of signing with City.

"Everything is going very well! I'll tell you more in a while."

City's previous record signing was Robinho, who arrived from Real Madrid for £32.5million as new owner Sheikh Mansour, a member of Abu Dhabi's ruling family, made a marquee signing to signal his intent just days after taking over in August 2008.

The Aguero deal is believed to be closer to £38million, the value of the buy-out clause inserted in the new contract the player signed with Atletico in January.

He is reportedly set to agree a five-year contract worth about £200,000 per week - although that will not be a stumbling block for City, who have spent millions revamping the squad and the area around the stadium with much grander plans to come.

With City striker Carlos Tevez adamant he wants to leave to be nearer his wife and two daughters in Argentina, Aguero is seen as the ideal replacement.

Younger than his compatriot by four years, the Atletico star has been a prolific goalscorer in the Primera Division and that is why he became one of the most sought-after strikers in Europe.

Atletico had resigned themselves to the fact they would lose their prized asset when he announced in May, before departing to play for Argentina in the Copa America, that he wanted to leave.

Aguero's preference was to remain in Spain, with city rivals Real seemingly the most likely destination, but Atletico were keen to resist such a move.

So an offer from City, although Italian club Juventus were also interested, represented a better option for the Madrid side.

Atletico coach Gregorio Manzano publicly admitted last night Aguero would not be returning to the Vicente Calderon.

"It seems as though in the coming hours we will have a final outcome to the issue that has occupied us for so long," Manzano told Spanish radio station Cope.

"It is already in its final stretch, I've asked the players to focus on Thursday's game (a Europa League tie against Stromsgodset).

"Unfortunately we won't be able to call on Kun (Aguero)."

While the club have yet to announce anything official, the player himself said the deal was done on his Twitter account tonight.

"I'm already a City player. Happy to be in this club and this city. Thank you all for the welcome and the reception!" he wrote.