Real Madrid allowed the striker to leave for Stamford Bridge in a deal worth £70m this summer.
Chelsea broke their transfer record to capture the Spain international.
And he has made a strong impact since arriving, scoring seven goals in all competitions for the Blues.
Antonio Conte had prioritised a move for Romelu Lukaku, but after Man Utd swooped, the Chelsea manager turned his attentions immediately to Morata.
The 25-year-old was bombarded with pleas it seems for him to go to Chelsea, and he is glad how things panned out.
Morata claims he even had interest from other Premier League teams beyond the Blues and United.
Morata told the Metro: ”Antonio, Michael [Emenalo], Marina [Granovskaia], all of them called me this summer and there was no chance I wasn’t coming to Chelsea.
“They demonstrated to me that they really wanted me.
“I had the chance to go to Manchester United and other teams in the Premier League.
“The important thing is I’m part of Chelsea and I’m very happy with this and now it’s time to fight for the blue shirt.
“I want to play well and win with this shirt.”
it is not clear which other Premier League teams were keen on him in the summer.
But Morata will have the opportunity tomorrow (4.30pm) to show Manchester United what they could have had.
Chelsea’s hitman has no bad blood with the Red Devils, though, and especially Jose Mourinho.
Morata revealed the pair still text regularly, having worked together at the Bernabeu.
Antonio Conte could be sacked if Chelsea lose to Manchester United
According to The Times Chelsea owner Roman Abramovich has paid a visit to Cobham training ground this week to speak with Conte. This has usually signalled that the manager is either facing or being close to get the sack. Could this be the last chance for Conte?
The Blues have suffered a handful of bad performances this season with a humiliating 3-0 defeat to AS Roma latest in mind, and are already nine points behind league leaders Manchester City after ten matches. In the Champions League the Blues are sitting firmly on the second place in the group C.
Chelsea’s volatile form this term isn’t all down to Conte though. It was the board’s fault for not getting him the signings he would have wanted this summer, and it’s all costing the team now.
Victor Moses, N’Golo Kante and Alvaro Morata have all suffered injuries during the season that have costed the side several points in the league. Rotating hasn’t been easy for Conte as he hasn’t had enough quality players available.
Kante is looking likely to make his return for Sunday’s crucial tie, which is a huge boost for Chelsea. Should United still be able to win though, Conte might find himself from the job centre on Monday morning.