"committed champion" is correct and usable in written English.
You can use it to describe someone who is passionate and dedicated to a particular cause or goal. For example, "She is a committed champion of social justice causes."
John was a deeply committed champion of government reform.
This is a shame, as Purnell has always been a committed champion of independent and experimental film, as well as a big film fan.
For a busy woman, Arianna Huffington, the co-founder and editor-in-chief of the Huffington Post, is a surprisingly committed champion of sleep.
"The American labor movement has lost a great leader today, and the Postal Service and its employees a committed champion and friend," he said.
Until he died in 2009, Mr. Kemp was a committed champion for more immigration, which he believed was at the center of the American experience; and he advocated a pathway to citizenship for those in the United States illegally.
A committed champion of contemporary British theatre, particularly during his time at the National when he nurtured the careers of Howard Brenton and David Hare as well as Pinter, Hall has more recently directed plays by Timberlake Wertenbaker and Simon Gray.
We are committed to championing the excellent care they provide and to use this as a driver so that excellence becomes the default standard in social care.
Councillor Roxanne Mashari said: "We are committed to championing the living wage and tackling the root causes of poverty in our borough.
Many health and care providers and staff have already committed to championing this programme and ensuring it works in practice and I strongly urge anyone working in health and care to do the same.
However committed its champions are to a major change, they should take the time to think through the full implications, as Trobe of the ASCL pointed out in his comments on the committee's report.
