Speaking to Sky Sports, Fletcher stated that he thought United were the better side despite the result and they paid the price for poor mistakes.
He said: "I feel like Man United have gifted the game to Wolves tonight.
"It has been their mistakes. I think they started the game fantastically. Wolves outplayed Man Utd in the FA Cup, that hasn't been the case tonight.
"United's mistakes in two or three instances have gave the game to Wolves and that's a disappointment. This is a bad loss for their top four aspirations
"I think they started in the ascendancy and as you say they looked in control.
"Even after the sending off they were in control with ten men.
"As I said before they've gifted the game to Wolves tonight, two individual mistakes, the red card, the first goal and even the second goals is individual mistakes from United.
"That's all United have done really. If you look back on the whole game, United have probably had the better opportunities, more of the possession but mistakes have been punished.
"It's a big difference from the FA Cup where Wolves were by far the best team. Tonight United were the best team but they've lost the game."