Top 25 U.S. Open rankings

Defying The Odds (3:25)

Casey Martin has defied all the doubters by qualifying for the US Open, all while dealing with a circulatory defect in his lower right leg. (3:25)

SAN FRANCISCO -- I've caddied in two U.S. Opens -- 2004 at Shinnecock Hills for Daniel Chopra and 2005 at Pinehurst No. 2 for Omar Uresti. Made the cut with both players and to this day say those were some of the greatest experiences of my caddying career.

Since the U.S. Open is the toughest test of golf, we decided that a top 10 list wasn't tough enough. So here's my top 25!

Michael Collins covers golf for ESPN.com. He can be reached at ESPNcaddie@gmail.com.