When the University of Maryland’s soccer season ended this past fall, Mikey Ambrose decided to start his pro career early. Though tempted by Europe and Major League Soccer, the junior defender from El Paso, Texas, ultimately joined the Austin Aztex, an expansion team in the third-tier United Soccer League.

That an acclaimed American prospect like Ambrose, a longtime member of U.S. youth national teams, would leave college for the U.S. minor leagues might have been unthinkable not long ago.

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