Soler, 20, inked a nine-year deal with Chicago worth $30 million, the New York Post and CBSSports.com reported.
The free agent -- seen as one the top Cuban prospects -- received bids from the New York Yankees and the Los Angeles Dodgers, the report said.
The 6-foot-3 rookie has played with several Cuban national teams and is expected to start his U.S. career in the minor leagues.
He is projected by Cubs General Manager Theo Epstein to be one of the cornerstones in his efforts to build the last-place Cubs into a National League contender.
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