Bielsa was without his first choice goalkeeper for the first time yesterday at Hull City, after the FA delivered the verdict in the case against Casilla on Friday evening.
An eight game ban, a £60,000 fine and 'face to face' education was the punishment meted out to the Spaniard, after an independent regulatory commission decided he was guilty of making a racist remark to Jonathan Leko in Leeds' game at Charlton back in September.
Although Bielsa did not wish to pass comment on the sanctions imposed on Casilla, instead preferring to let the player, the club and the authorities all say their piece, he had a lot to say about his keeper's character.
Everyone at Leeds United is against racism, Bielsa said, and the governing body's decision must be accepted.
"The authorities have expressed themselves, Kiko has also and the club, I think any contribution I can make is not significant," he said.
"I think that we must accept the rules of the competition and accept those decisions.
"All of us are against every kind of racism and discrimination, this is very clear."
READ: 'Devastated' Casilla reacts to FA banEqually, everyone at Leeds United will support Casilla because Bielsa feels that is what the former Real Madrid man deserves.
"The effect his sanction has on his spirit is clear, it is not just something professional, if something has impact on his behaviour and personal matters," said the Argentine.
"Kiko is a great human being and to people like him a situation like this of course affects him.
"But I think he is strong and all of us will support him, fundamentally with the love that he deserves because I want this love between us."
Bielsa gave no detail on what the club's plans are for the keeper during the ban, nor would he pass comment on the specifics of the incident in question, but he did speak of Casilla's unblemished past record, his conduct since arriving at Elland Road from the Bernabéu in January 2019 and his treatment of minority groups,
"We, more than the professional concept we have of him, we admire him for his behaviour with us," said Bielsa.
"He has a brilliant past with nothing negative, he played in one of the best clubs in the world and he joined us with a humility that points to the kind of person he is.
"Also I saw a lot of behaviour of Kiko where he supports the minorities, those excluded from society and of course he doesn't do this publicly.
"But when the behaviour of one person is analysed, we really know that he has great behaviour in the human sense.
"I am not in good condition to talk about the situation he has, this is something I know, the club knows and the authorities who judge him know.
"All of us are against racism, he is the first one but from now he will receive all the love he shares with us, from us to him."