2021 MLB mock draft 1.0: Kumar Rocker to Red Sox, Pirates go with a catcher at No. 1 in Keith Law's first look - The Athletic
2021 MLB Draft — MLB Draft — Prospects Live
Red Sox prospect Marcelo Mayer hits first homer of season for Greenville Drive
2021 MLB Draft: Red Sox first-round pick Marcelo Mayer quickly ditches Yankees allegiance
Red Sox No. 1 Prospect Marcelo Mayer Promoted to Portland
MLB Draft 2021: Marcelo Mayer and Five Other Prospects to Watch - The New York Times
Red Sox first-round draft pick Marcelo Mayer wants to sign 'as soon as possible' - The Boston Globe
2021 MLB Mock Draft 2.0: Jack Leiter to Tigers, Pirates take a high school shortstop in Keith Law's latest look - The Athletic
As Red Sox shut down Marcelo Mayer, rival prospects take off – NBC Sports Boston
2021 Florida Complex League Top 10 Prospects — College Baseball, MLB Draft, Prospects - Baseball America
Red Sox' Marcelo Mayer vaults into top five on MLB's Top 100 Prospects list – NBC Sports Boston
Red Sox prospect Marcelo Mayer out for rest of 2023