Manchester United started the game poorly and found themselves 1-0 down after just 11 minutes thanks to Callum Wilson’s opener.
However, Anthony Martial continued his good recent form when he netted an equaliser in the 35th minute at the Vitality Stadium to leave the score at 1-1 at half-time.
Mourinho opted to introduce by Herrera and Marcus Rashford in the second half, with both players coming on in the 56th minute and making a difference in the top-flight clash.
Rashford ended up netting the eventual winner late on to claim all three points for the Red Devils as they made it back to back wins in the Premier League for just the second time this season.
And speaking to BT Sport after the game, Mourinho paid credit to Herrera for the impact he made after coming on early in the second half.
“The first half was a disaster,” said Mourinho. “The second half was much better. We created lots of chances and deserved to score before the 92nd minute.”
Asked about his team talk at half-time, Mourinho continued: “I started off positive. I said it is impossible to play worse than we did so the second half will be better for sure.
“I was happy bringing Ander Herrera into the game.
“I felt we needed him to give more balance and to recover the ball faster. I was happy with that change. It was much better.”
Manchester United will now turn their attentions back towards Champions League affairs and their trip to Juventus on Wednesday night.
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