The Meon Valley Golf Club talent’s team won the competition by 16 shots at Magnolia Grove Crossings, Alabama.
Ellis fired on all cylinders and was individually crowned tied leader.
The 2017 British Amateur champion finished on 11-under par, after carding rounds of 69, 67 and 69.
Ellis’ achievements in the college game have seen him shortlisted for the prestigious Ben Hogan Award.
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He’s the only player from Florida State University to be nominated alongside 26 other golfers across America.
The shortlist will be narrowed down to 10 players on April 11.
Former winners of the Ben Hogan Award include Rickie Fowler, John Rahm, Billy Haas and Hunter Mahan.