you missed this press release
http://thecup.us/us-soccer-unveils-2010-lamar-hunt-us-open-cup-format/single elimination, winner advances to next round. We woulnt see a MLS team until June 29
June 15: First round – 32 lower-division teams (USSF D-2, USL-2, amateur)
June 22: Second round – 16 first-round winners
June 29: Third round – Eight second-round winners plus eight MLS teams
July 6 or 7: Quarterfinals – Third-round winners
Aug. 31 or Sept. 1: Semifinals – Quarterfinal winners
Oct. 5: Final – Semifinal winners
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