Boucher acknowledged that Rabada should have been more aware that previous transgressions put him in danger of a ban
South African coach Mark Boucher said on Friday he was "concerned" about cricket's disciplinary regulations after fast bowler Kagiso Rabada was handed a ban which means he will miss the fourth and final Test against England in Johannesburg next week.
"I am concerned, to be honest," said Boucher. "You don't want to take all the aggression out of the game. You've got two countries playing against each other in a heated situation. Guys are trying really hard."
But Boucher acknowledged that Rabada should have been more aware that previous transgressions put him in danger of a ban.
Rabada pleaded guilty to a level one breach of the International Cricket Council's code of conduct because of the way he celebrated the dismissal of England captain Joe Root during the first day of the third Test at St George's Park on Thursday.
He was fined 15 percent of his match fee and handed one demerit point. Because it was his fourth demerit point in a 24-month period he incurred an automatic one-match ban.
"Level one is almost like a slap on the wrist but because of the demerit points unfortunately he won't be playing in the next Test," said Boucher.
"Sometimes the emotions overflow so the rules and regulations are a little disappointing but if you know the rules and regulations you’ve got to stick to them. KG (Rabada) knows what he can and cannot do and he maybe pushed a little far."
Boucher said losing Rabada was a "massive blow" for a South Africa side in danger of falling 2-1 behind in the series after closing day two in Port Elizabeth on 60-2 in reply to England's 499-9 declared.
He said it was an issue that needed to be addressed.
"I think KG probably bowls at his best when he is nice and aggressive so it's trying to find a balance of keeping him aggressive and not boxing him in, but also understanding the laws of the game and trying to keep him on the good side of it.
"It is going to be tough but it is something we are going to have to address and get a very good balance."
Boucher said the game had changed since he stopped playing in 2012.
"In my day we didn't have to deal with this sort of stuff because we could say pretty much what we wanted and get away with it. It's a learning curve for me with all these new rules and regulations."
Rabada was criticised by former West Indian fast bowler Michael Holding and former England batsman Kevin Pietersen but the ban was slammed by ex-England captains Nasser Hussain and Michael Vaughan.
Holding and Pietersen said Rabada had let his team down by being a repeat disciplinary offender.
"He has to learn," said Holding, who was commentating for SuperSport television.
"You can't keep making the same mistakes. He has to remember he is damaging his team. South Africa without Rabada at the Wanderers –- that's a big blow."
Fellow commentator Pietersen said the way Rabada got close to batsmen after dismissing them was unacceptable.
"I am concerned, to be honest," said Boucher. "You don't want to take all the aggression out of the game. You've got two countries playing against each other in a heated situation. Guys are trying really hard."#SAvENG— SuperSport 🏆 (@SuperSportTV) January 18, 2020
"He shouldn't be celebrating in a batsman’s personal space," he said, adding that Rabada had behaved in a similar way after dismissing Zak Crawley during the second Test in Cape Town.
"I feel sorry for (South African captain) Faf du Plessis and Mark Boucher," said Pietersen. "South Africa are going to miss their strike bowler at the Wanderers."
But Vaughan said on Twitter that Rabada being banned for a celebration was "absolutely bonkers" when nothing was done about slow over rates, while Hussain said on Sky television that "the game has kicked itself today".