In Last Bus to Wisdom, when they are at the Crow Fair and looking at the Fancy Dancer's eagle feather circle, Slewfoot tells them that it once belonged to a high school student who would wear it at the basketball games. He would stand at the top of the bleachers and spin around making an eagle cry. This was big magic and helped the team win the championship. There was no mention of a particular player.
In the Acknowledgements chapter, Doig says, "At the time of this story, 1951, the small Blackfeet Reservation community of Heart Butte had no high school and hence no Heart Butte Warriors team of famous basketball proficiency as I portrayed. But since then, Heart Butte has attained a high school and the Warriors have twice been Class C state basketball champions, and example of life copying art that can only make an author grin."
Perhaps your friend was mentioned in another Doig book. Glad I still had the book here so I could answer your question. 
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