Red Sox promote top infield prospect Marcelo Mayer The Boston Red Sox are officially calling up top infield prospect Marcelo Mayer, MassLive’s Katie Morrison-O’Day first reported Saturday. Mayer is currently listed as the Red Sox’s No. 2 prospect and the No. 8 prospect in MLB, according to MLB Pipeline. He was listed as Fangraphs’ 31st-best … Continue reading Red Sox promote top infield prospect Marcelo Mayer