Gary Neville said the speed of Ruben Amorim's exit from Manchester United had come as a "shock" after the Portuguese boss was sacked on Monday after 14 months in charge.
Amorim left Old Trafford with the struggling Premier League giants sixth in the table after Sunday's draw at Leeds which followed a woeful 1-1 result at home to basement club Wolves.
Amorim, 40, has the lowest win per centage – 31.9 per cent – of the seven managers who have taken charge at Old Trafford since celebrated boss Alex Ferguson stepped down in 2013, when the club last won the Premier League title.
His dismissal followed growing tensions with Old Trafford bosses, including director of football Jason Wilcox, over recent days.
Amorim also he made a string of eye-catching comments after Sunday's draw at Elland Road, where he stressed he was United's manager rather than "just the coach".
The Portuguese told the scouting department and Wilcox "to do their job" during a blockbuster finish to a post-match press conference that raised major doubts over his future.
Former United and England full-back Neville, now a well-known television pundit, told Sky Sports News: "When a manager is sacked, it’s a poor reflection on everybody. It means it's not worked.
"Ultimately everyone loses, particularly when you are sacking a manager partway through the season. It’s very difficult to get an adequate replacement in.
"I am surprised it's happened this morning, I'm not surprised it's happened. I didn't realise it would happen so quickly. I did think they'd get through another couple of weeks and try and work out what to do.
"If you look at some of the performances in the last month, they've really been shocking... The Wolves game seems to me to be the killer game. It was a bad one, that," the 50-year-old added.
Former England striker Gary Lineker said Amorim was the wrong man to manage a club he labelled a "basket case".
"I think it was almost as though he provoked it," Lineker told the Rest Is Football podcast.
"It didn't seem to be the right fit and he was a bit stubborn about the way he wanted to play.
"The players didn't suit the way he plays and the club should have recognised that.
"I suspect they haven't supported him in the sense of bringing in the players he would have wanted in certain positions.
"Also, it's been bit of a basket case of a football club over the last few years."
United defender Harry Maguire wished Amorim well on Instagram, posting a photo of the two of them clasping hands accompanied by the message: "Thank you for everything boss. I wish you all the best in the future."