Steve Bruce has been the "fall guy" at Newcastle and it has been "really tough to watch" the criticism directed at him, says his son Alex Bruce.
The Newcastle boss takes charge of his 1,000th match as a manager at home to Tottenham on Sunday.
It is the Magpies' first game since the club's controversial £305m takeover.
Steve Bruce took the role at his boyhood club in 2019 but his son says he "has been battered since the moment he walked in the door".
"It's been tough. I wouldn't sit here and lie and say it hasn't, it's been really tough to watch the criticism," Alex Bruce told BBC Radio 5 Live's Football Daily podcast.
"Since he took the job, I think the lack of respect that has been shown, considering he's done 1,000 games, has been unbelievable."
New Newcastle part-owner Amanda Staveley confirmed on Friday that Bruce would stay in charge for Sunday's Premier League game at St James' Park and would be the "first to know" if things change.
The Magpies are winless this season and lie 18th in the table. The club's new owners have been linked with former Borussia Dortmund manager Lucien Favre, Rangers' Steven Gerrard and ex-Chelsea boss Frank Lampard as potential replacements for Bruce.
Alex Bruce added: "A lot of things have been said about my dad, and I feel a bit naff sticking up for him, but I would genuinely say for anyone who has done 999 games as a manager, 980-odd as a player, to see certain individuals question his integrity, his professionalism, his ability as a manager, questioning things like his warm-ups, his substitutions… they all make mistakes, but has he not deserved a crack?
"He's never had the opportunity at managing a club who can go and spend proper money. He's managed teams in the Premier League like Wigan, Birmingham, Hull City… his win ratio in the Premier League has been questioned umpteen times - do people really expect massive win percentages when you're managing clubs like that?
"I don't think so. I think when you're a level-headed and intelligent person, you look at the bigger picture. I think he's done a very good job at all the clubs he's managed, and I think he deserves a crack. Some of the disrespect he's been shown has been hard to watch."
'I know what Newcastle means to him'
Since replacing Rafael Benitez as manager at St James' Park in July 2019, Steve Bruce has led Newcastle to 13th and 12th-place finishes in the Premier League.
The Saudi Arabian-backed takeover of the club was completed last week, bringing an end to Mike Ashley's 14-year spell as Magpies owner.
Steve Bruce has come under increasing pressure in recent weeks and a large proportion of fans want the 60-year-old to leave the club, and former Ipswich, Leeds and Hull defender Alex Bruce says he expected the heat from the start.
"He knew that was going to be the case from the day he took the job," he said. "He had an owner who was trying to sell the club, he had an owner who didn't really want to put any money of his own into the club for a number of reasons, he could only use the money that the club generated and with the pandemic there wasn't any money there.
"He tried to strengthen the squad in the last window. They desperately needed reinforcements in defensive areas, I think he was very frustrated he couldn't do that, so there's been a number of things that have made the job difficult.
"He has been the fall guy. The amount of times I've said to him 'why don't you let someone else do the press?' and he just says 'because I'm the manager, it's my responsibility'."
Newcastle finished 10th and 13th in Benitez's two full seasons with Newcastle in the Premier League and Alex Bruce believes that the Spaniard was given greater respect for what he achieved.
He said: "Dad's finished round about similar and yet one's been lauded as a messiah and the other one's been battered since the moment he walked in the door, which has been the most difficult thing for me to watch because he's a Geordie.
"I know for a fact, no matter what people say, what Newcastle means to him as a fella. He used to crawl under the turnstiles, stand there when he was a kid with his dad, he's always supported the club.
"No matter what you say about my dad, he thinks a lot of the club and he knows more than anybody that this new ownership has needed to happen and believe me, he is absolutely delighted that it has, not just for the football club, but for the city and the supporters as well."
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