Paul Pogba believes it was his "destiny" to return to Manchester United.
The France international midfielder moved back to Old Trafford from Juventus for a world-record transfer fee of £89m (105m euros) on Monday night, four years after making the move the other way.
He admits there was some sadness to leave Italy, where he won four Serie A titles, but that he always wanted to return to Manchester where he felt there was unfinished business.
"I think it's destiny, I would say it's destiny," he told MUTV. "First my mum told me I would come back here and I told her, 'You never know, you'll see.' For myself as well it's a big challenge too, just to come back to where I came from, where I grew up, where I started.
"I didn't finish what I started here so I think I came here to finish it."
Pogba says his focus now will be on helping Manchester United rediscover their ability to win league titles, and that he is ready to "just kill it" at Old Trafford.
Manager Jose Mourinho spoke about the French midfielder being a player around whom his side could be built for "the next decade" and Pogba wants to become one of the best the club has ever had.
"The thing with me is I only think about the pitch," he said. "I want to do great, I want to be one of the best, I want to win titles, I want to achieve things and that's all; that's why I came here, just to do this, to become one of the best and to win titles because I know this club has to win titles.
"This club is created to win titles, to win things, to win big things. I just focus on this and that's it. I'm just ready to go and work on that and just kill it."