A-Rod's business partner, Jose More, confirmed that the sale closed Friday.
Rodriguez bought the 54,000-square-foot piece of waterfront land for $7.4 million in 2010. Using his own construction company, Newport Property Construction, he spent another $7.6 million building a nearly-20,000-square-foot mansion.
The sale -- one of the highest ever in Miami-Dade County -- will earn Rodriguez a $15 million profit.
More says Rodriguez decided to sell because the buyer, who More wouldn't name, made A-Rod an offer he simply could not refuse. More says Rodriguez also loves the design process and is already planning to buy another home in South Florida with a little more privacy.
A-Rod is recovering from surgery on his left hip.