Real Madrid defender Antonio Ruediger "has to change and he knows it himself," Germany sporting director Rudi Voeller said on Monday, following the player's behaviour in the Copa del Rey final.
Germany centre-back Ruediger was substituted in extra-time of Sunday's 3-2 Clasico loss to Barcelona before being sent off for throwing an object at referee Ricardo de Burgos Bengoetxea.
The 32-year-old had to be held back from confronting the official by fellow Madrid players and staff as he was shown a red card, with teammates Lucas Vazquez and Jude Bellingham also dismissed at the end of the game.
"Toni is an exceptional footballer and a very emotional guy, a fighter on the pitch. He has to stay that way," Voeller told German news agency SID, a subsidiary of AFP.
"But in this case, he and some of his teammates let themselves be influenced too much by the extremely tense atmosphere around the club," he added.
Before the final, Bengoetxea and VAR referee Pablo Gonzalez Fuertes complained about attacks from Madrid's club television channel on officials this season.
"This can't happen. Especially not as a player for the German national team. He has to change that and he knows it himself, as his public reaction shows," former Germany coach Voeller said.
On Sunday, Ruediger apologised for his actions.
"There's definitely no excuse for my behaviour last night. I'm very sorry for that," Ruediger said on social media.
"After 111 minutes, I was not able to help my team anymore and before the final whistle, I did a mistake. Sorry again to the referee and to everyone I have disappointed last night," he added.
Voeller said the German international contacted him and Germany coach Julian Nagelsmann on Sunday.
"We discussed the situation for a long time," said Voeller.
He said an exchange also took place internally within the German Football Association (DFB).
"Toni is an excellent player, but as a national team player, he must also show class in his behaviour," Voeller said.
"He rightly demands respect for himself. This respect he must also show to others without exception," the ex-Germany striker added.
'SUSPEND HIM'
Other former German internationals rushed to voice outrage or support.
Ex-Germany captain Lothar Matthaeus, who holds the national team appearance record, demanded action.
"He lost his mind," Matthaeus told German broadcaster Sky. "He was out of control. I expect a XXL suspension."
Matthaeus pointed out Ruediger was already under scrutiny after receiving a one-match ban from European governing body Uefa for a throat-slitting gesture after netting a penalty in a shootout win over Atletico Madrid in a Champions League victory in March.
Ruediger faces a suspension of between four and 12 matches under Spanish Football Association rules, but SID said he is not expected to be sanctioned by the DFB.
Dieter Hamman, a midfielder who played 59 times for Germany, also called for the DFB to act.
"I think the DFB should suspend him. I wouldn't consider him for the Nations League finals, so I would suspend him for two matches," Hamann told German channel Sport 1.
Former Germany goalkeeper Jens Lehmann disagreed.
"He became such a great player because of who he is. And if we try to take that away from him now, he might not be able to reach his full potential. I'm not sure we can afford to do without him," said Lehmann on Welt TV.
Germany host the final four of the Nations League, and will play a semifinal against Portugal on June 4 in Munich and a final or third-place play-off four days later.