One of a list of facts Harry Potter learns about Quidditch from a book:
...シーカーは普通一番小さくて速い選手がなり、大きな事故といえばシーカーに起きやすいこと、...
He learnt that ... the Seeker is normally the smallest and fastest player, and big accidents easily happen to the Seeker ...
I'm confused by がなり in this sentence. I'm assuming this is particle が plus the 連用形 of なる but, if so, what is the 選手 becoming? There is nothing marked by に.
My best guess is that there is an implied シーカーに before なり. So a clunky translation would be "As for the seeker, the smallest and fastest player usually becomes it/the seeker". Is this correct? I don't think I've seen such a construct before.