Steve Bruce has claimed Hamza Choudhury could have ended Matt Ritchie's career with the "horror" tackle which left him facing two months on the sidelines.
The 21-year-old Leicester midfielder, who signed a new four-year contract on Friday, left his Newcastle counterpart with ankle ligament damage and three wounds which needed stitches, the result of a forceful challenge during Wednesday night's Carabao Cup second round clash at St James' Park.
Referee Tim Robinson booked the Foxes player, much to the astonishment of Magpies head coach Bruce, who was convinced it merited a red card.
Asked if the fact Choudhury won the ball was a defence, he replied: "No chance. He went over the ball, which makes it dangerous.
"They are the ones that really... if Matty hadn't taken [his leg] away, he'd seen it coming, he could have been in serious trouble.
"It could have been eight months, it could have been career-ending. If his leg had been planted on the floor, he was in serious trouble. He rode it a little bit, but it was a horror challenge.
"You can't tackle like that any more. When you leave the floor, you are over the top of the ball in your follow-through. Sorry, but it is a bad challenge."
Ritchie is likely to miss around eight weeks of the season starting with Saturday's Premier League fixture against Watford on Tyneside, robbing Bruce of one of his most dependable performers.
The 58-year-old admires Choudhury – who was sent off on England Under-21s duty against France during the summer for another challenge – as a player, but hopes he learns from the incident.
He said: "He is a very, very good player. He is enthusiastic and wants to go and win the ball back. I've got nothing against that, I liked that sort of thing myself.
"But it is a bad challenge and I hope he learns from it."
Choudhury was unrepentant when asked about the challenge in a television interview, citing Bruce's own uncompromising style during his playing days.
However, the former Manchester United defender said: "I never went over the ball. Never. I can't remember injuring anyone either."
