Mourinho really, really wanted a central defender before the window slammed shut with a bunch of names linked with a transfer to Old Trafford. It was no escape, but rather the thrill of a new challenge.
Boateng actually lined out against United in a pre-season friendly on August 5 and must have impressed Mourinho but the German worldwide never looked keen on a return to Manchester.
The Mirror reported last month that United held talks with Bayern Munich over a potential £44.5m deal to sign the German World Cup victor following their friendly at the Allianz Arena in early August but once again they failed to get a deal agreed.
And Boateng confirmed that the former Frankfurt coach was one of the factors keeping him. However, despite being tempted by a new challenge, the defender explained that it wasn't easy for him to leave a club like Bayern Munich. I feel well at Bayern.
"As a fan, honestly, part of me is that no one is bigger than the club and I am not interested in people who are looking left and right. Everything has to fall in place to top this club, if I do it. Niko Kovac gave me the feeling that I am very important for him and the club".
Boateng, who has previously played for Manchester City, attracted interest from United and French champions Paris Saint-Germain during the transfer window, but chose to remain at Bayern.
With time running out and Mourinho still keen on signing a centre-back, the Portuguese manager looked elsewhere.
This summer's World Cup saw Pogba showcase exactly why Mourinho splashed out £89m to sign him from Juventus in 2016.