supplemental draft - 美式足球

剛在Yahoo Sports看到的新聞
In using their 2007 third-round pick to select former Virginia standout
Ahmad Brooks in the NFL supplemental draft, the Cincinnati Bengals added
a more physical presence at inside linebacker.

啥是supplemental draft? 以前不都是由聯盟根據各隊走掉的Free agent
跟簽來的free agent再補償球隊supplemental draft嗎？
而且是用在當年。
為什麼這次Bengals居然用2007年的選秀權來選Ahmad Brooks?

新聞連結
http://sports.yahoo.com/nfl/news?slug=jm-supplemental071306
&prov=yhoo&type=lgns

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