The Spain international completed a move to Ligue 1 champions Paris Saint-Germain last week after his contract expired at Manchester United.
Herrera was a popular figure amongst the Manchester United supporters for his tenacious style of play in the heart of the midfield.
Louis van Gaal recruited Herrera in a £29m deal from La Liga side Athletic Bilbao in the 2014 summer transfer window, but the 30-year-old produced his best performances under his successor Jose Mourinho.
The Portuguese coach was replaced by Ole Gunnar Solskjaer in December – and the Norwegian coach did use Herrera as a squad player in the second half of the season.
However, Manchester United failed to tie down Herrera to a new deal despite his contract entering the final months.
Herrera completed a move to Ligue 1 giants PSG from Manchester United last week after a lot of speculation about his situation.
And the Spanish midfielder has finally broken his silence about his departure from the Old Trafford outfit.
“I don’t like looking at the past but there were differences regarding the project and my importance within it. I was very happy, I have a lot to thank the club for, the fans and also Solskjaer,” Herrera told Marca, as quoted by Metro.
“He (Solskjaer) did a lot for me to stay, but things didn’t happen. They arrived late and, by then, I’d already made the decision to play in Paris.”
Manchester United have signed Swansea City midfielder Daniel James and Crystal Palace defender Aaron Wan-Bissaka in the summer transfer window.
The Red Devils finished in sixth spot in the Premier League table last term.
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