madrid's defeat over sociedad, did not destroy the mentality of the madrid players, rodrygo successfully scored 2 goals, which at the same time made madrid win over osasuna, even though osasuna had been waiting for the copa del rey trophy since decades ago. Facing Man City in the UCL match will definitely put a lot of pressure on Madrid because Man City will definitely try hard to get rid of Madrid in the UCL in any way possible, maybe Pep will use the strategy used by Sociedad to beat Madrid.
Real Madrid deliberately lost to Sociedad because they wanted to focus on the Copa Del Rey final, which was against Osasuna and ended up being won by Real Madrid. Currently, the Copa Del Rey League match has finished, and maybe Real Madrid will return to focus on the UEFA Champions League because of the opponents they face very hard. Manchester City has several mainstay strikers who are very difficult to stop, and I'm sure Real Madrid will implement a full defense in the match against Manchester City.
There's no way a top club like Real Madrid would want to lose a certain match because they've got another more important match to play. The defeat Madrid suffered against Real Sociedad was caused as a result of wrong team rotation from the manager who must have thought his selection of players for that game would still earn him the win he needed considering Sociedad's quality.
The Copa Del Rey win yesterday was needed to mentally strengthen the team ahead of their Champions League semi final clash with Manchester City and to also hand the them their first major trophy of the season.