The Boston Red Sox call up top prospect Marcelo Mayer after Alex Bregman's quad injury.

The Boston Red Sox are calling up top prospect Marcelo Mayer after Alex Bregman was injured with quad tightness. Mayer, a 22-year-old shortstop hitting .271/.347/.471 in Triple-A, will provide infield help for the Red Sox. His promotion comes as Bregman's return date is uncertain, and Mayer's strong performance in the minors could give the team the boost they need.