But, despite the massive investment, City is clinging to fourth place in the Premier League heading into the final week of the season; Arsenal is three points behind with two games remaining.
Guardiola took over at the Etihad at the start of the season after trophy-laden spells in Spain and Germany had confirmed his status as one of the world's most sought-after coaches, but finding success in England has been harder to achieve. It will probably be my last game in a City shirt in front of the fans. I want to make the right decision for myself, for my family and for the club.
"When I first came to Manchester I felt like when I was in Barcelona at Espanyol - we were not the main club in the city", he said. "At the clubs I worked at before I am not here [for the following season], but here we have a second chance and we will try to do it better than this season".
Keep up to date with ALL the Manchester City news, gossip, transfers and goals on our club page plus fixtures, results and live match commentary. I don't know how many chances we created or how many times we arrived.
"But, of course, if he asks me for advice I would tell him to stay - he's a great player". I'm out. If it is Barcelona and Bayern, you don't win and you are out.
Yaya Toure scored perhaps a farewell goal for the club, and the team virtually guaranteed a place in the Champions League.
Guardiola was referring to Argentinian defender Pablo Zabaleta, who played his last home game for the club prior to leaving as a free agent.
After the game, Guardiola showed up late to his post-match press conference but, to be fair to the Spaniard, he had a pretty brilliant excuse for his tardiness.
Manchester City enter the final weekend of the Premier League season with their top four hopes very much in their own hands.
"A lot is said, and I have a good relationship with Guardiola from the times at Barcelona, but I should be focused on my club". Facing Albion is never easy, but who said it was easy?
City also beat United to the Premier League title in 2012 in dramatic fashion when Sergio Aguero's injury-time victor snatched the trophy out of their rivals' hands on the final day of the season.