The 22-year-old was linked with a move to Old Trafford when it became clear that he would be leaving his Argentine club, but Manchester City ultimately won the race to sign him.
Alvarez remained on loan at River for the second half of the 2021-22 campaign before moving to the Citizens, and he has scored three times in eight appearances for the English champions.
According to Italian journalist Fabrizio Romano, Rangnick, who was Man United’s interim head coach at the time, asked the Red Devils to sign the Argentine.
However, the 20-time English champions decided that they were not in the market for a centre-forward, which ultimately allowed Man City to acquire his services in the latter stages of the window.
“The 2023 January transfer window will be an important one for the club’s project,” Romano told CaughtOffside. “But for it to be a success they need to learn from the mistakes of last year.
“The mistake was clear: Ralf Rangnick, who was at that time interim manager and preparing to become a consultant to work with the board and with Erik ten Hag, was furious with Man United because they didn’t want to sign any players last January.
“They had some opportunities, but they didn’t want to sign a striker, specifically. Julian Alvarez was of one of those players – he was offered to United and other clubs.
“He had a release clause, and was a player Rangnick had on his list at Lokomotiv Moscow. In the end, Man United decided not to proceed. And now Man City have this really good striker, for the present and the future.”
Rangnick was expected to remain with Man United on a consultancy basis following the end of his time as interim head coach.
The 64-year-old was set to balance managing the Austria national team with his position at Old Trafford, but it was eventually revealed that he would be cutting ties with the Red Devils.
“We would like to thank Ralf Rangnick for his efforts as interim manager over the past six months,” read a statement on Man United’s official website at the time.
“By mutual agreement, Ralf will now focus solely on his new role as manager of the Austria national team and will not therefore be taking up a consultancy role at Old Trafford. We would like to wish Ralf the best of luck in this next chapter of his career.”
Rangnick previously acted as head of sports and development for Red Bull, working with both Red Bull Salzburg and RB Leipzig, while he was manager of sports and development at Lokomotiv Moscow before moving to Old Trafford to replace Ole Gunnar Solskjaer.