The answer is Real Madrid.
Regarding Real Madrid, two managers of Manchester United have made famous quotes that are enough to be passed down from generation to generation: Ferguson - "I will not sell a single germ to Real Madrid", Busby - "Manchester United is my paradise" .
Everyone should be very clear about the story between the former and Real Madrid. Beckham, Van Nistelrooy, CR, well, your devil has now become a satellite club of Real Madrid. No wonder the stubborn old Scottish man said this. In absolute terms, well, let's ignore for the moment what a very angry old man said and talk about Busby.
Do you know why Busby said "manchester is my heaven"? That's because the Bernabeu (Chairman of Real Madrid), who had a good relationship with him at the time, invited him to coach Real Madrid and promised to provide Busby with a "football paradise", so the great Busby said this Great words to come.
After the Munich air disaster, Manchester United did not receive any financial assistance. Real Madrid offered to lend Manchester United a loan but was rejected by Manchester United. Afterwards, Real Madrid proposed to award the 1958 Champions League trophy to Manchester United ( At that time, Belgrade also seconded the proposal. I think there were more than one, but I couldn't find the specific information), but it was rejected by UEFA. However, Real Madrid, who eventually won the Champions League that year, gave the trophy to Manchester United.
Before the plane crash, Manchester United once asked to buy Puskas (see clearly, it is Puskas, but I personally think that Manchester United cannot actually afford him). After the plane crash, Real Madrid proposed to buy him. Puskás was sold to Manchester United (I didn't check whether it was a discounted price or something), but the move failed because of the FA's "players must speak English" policy at the time. If the trade doesn't work, then rent. This is another plan proposed by Real Madrid, but Puskas is a generational football champion. This time, it is the British salary cap that hinders the Hungarian's arrival.
As mentioned before, Manchester United did not receive any financial assistance during the reconstruction period. But the smart Busby found another way. The method he gave to the Bernabeu was a friendly match. (It is said that after receiving the call, the Bernabeu immediately asked his female secretary to arrange the time, which shows how much attention was paid to it.) Real Madrid's influence was too great at that time. Playing friendly matches with Real Madrid made a lot of money for both of them. It means a lot to Manchester United. What's more valuable is that Real Madrid not only agreed to Busby's invitation, but also played friendly matches with Manchester United for five consecutive seasons. Moreover, these games were all held during the season, and Real Madrid only received half of the appearance fee. .
By the way, in the 1957 Champions League semi-finals, Real Madrid VS Manchester United, 5-3 in two rounds, Real Madrid advanced (drawed 2-2 at home; lost 1-3 away from Real Madrid), The busby Babe It's the first time he has shown his talents, but it's a pity that God is not beautiful.
(The era when scores were all written by hand)
Ten years later, the two teams met again in the 1968 Champions League semi-finals. This time the Busby Babies were reborn 4- 3 victory over Real Madrid (1-0 Real Madrid at home; 3-3 draw away from Real Madrid). Bath also took off his hat to the Real Madrid fans after the game. Such a story now seems to be really legendary and worthy of Manchester United fans and Real Madrid fans. Fans will always remember it...