Pep Guardiola warns Manchester United amid cheeky Wayne Rooney offer

Pep Guardiola said that Manchester City have achieved the biggest prize in football by sustaining their success over many years.

Sir Jim Ratcliffe has spoken warmly of City's achievements after investing in Manchester United and the Reds have already taken a key member of City's staff in poaching Omar Berrada to become their new CEO. City repeated United's Treble when they won the Premier League, FA Cup and Champions League last year and are in with a chance of defending all three crowns; a fourth Premier League title in a row would also be unprecedented.

Guardiola has welcomed the new challenge from Ratcliffe but amid talk of teams being knocked off perches the City boss said that City's biggest landmark has taken eight years of hard work. Unless United are prepared to put in a similar effort, they will not be able to compete with the very best.

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"You don’t have success if all the elements of the club are not together, it’s impossible. It doesn’t belong to one player, one manager, one anything. It belongs to all the details have to be on the same path, aligned, all of them, otherwise it’s more difficult. Not difficult for a short period, but for a long period, it’s impossible," said Guardiola.

"The proof we are doing the most difficult thing in sport is people believe you have to win and win. And being there for a long, long time, you cannot deny," he said.

"Still, we are there after seven or eight years. Few clubs can do it and still we are there. That is why it is the biggest title, prize, and everything. And the biggest contenders they know it, how difficult it is."

Guardiola was thrilled