Rosenbaum then attended
Pomona College, where he played on its
NCAA Division III baseball team the
Pomona Sagehens as a
pitcher and
infielder, and double-majored in Mathematics and Economics. As a sophomore in May 2014 Rosenbaum was named to the NCAA Division III Capital One District 8 Academic All-District Team. In 2014 he was named an
All American and
SCIAC Player of the Year, as well as a member of the SCIAC Baseball All-Academic Team and West Region Player of the Year. In the summer of 2014 he played for the
Wenatchee AppleSox of the
West Coast League. He was named 2015 All-SCIAC First Team, and named a 2015
Jewish Sports Review College Baseball All-American with, among others, first baseman/outfielder
Jeremy Wolf and designated hitter/pitcher
Jake Fishman. For his senior thesis, he evaluated the impact of the Major League Baseball
collective bargaining agreement on the first-year player draft. For his college career he batted .376 with 23
home runs, 64 doubles, and over 160
RBIs, while pitching to a 7-3 record. In 2015 Rosenbaum played for the
Vermont Mountaineers of the
New England Collegiate Baseball League. He batted .245/.288/.327 with no home runs and six RBIs in 49
at bats. ==Brussels Kangaroos==