Complex sentence: He advanced to the semifinals of the 2008 U.S. Amateur, where he lost 3 & 2 to eventual U.S. Amateur champion Danny Lee--the top-ranked amateur in the world.
Split into simpler sentences: He advanced to the semifinals of the 2008 U.S. Amateur. He suffered a 3 & 2 loss to eventual U.S. Amateur champion Danny Lee--the top-ranked amateur in the world.