Marcelo Mayer was unceremoniously thrust into the spotlight once the Boston Red Sox officially lost Alex Bregman in free agency, with the expectation being that the former top prospect would have to carry on the lineage of great third baseman that had defined the franchise's recent history.
Caleb Durbin wound up winning that job after coming over in a late-offseason trade with the Milwaukee Brewers, but that didn't take any pressure of Mayer to perform. The 23-year-old was trusted with an Opening Day roster spot as the starting second baseman, with the hope being that he'd play well enough to remove any interim tag from that label.
Well, you can mark at least one former Red Sox star down in the camp of believers, as retired reliever Jonathon Papelbon forecasted Mayer taking over as the full-time second baseman by the end of May.
"I think eventually, they're going to hand this kid the torch... the biggest difference between him and Roman Anthony is Marcelo Mayer doesn't have the plate discipline that Anthony does," Papelbon said during an appearance on the "Foul Territory" podcast.
If that prediction comes to pass, the Red Sox will be sitting real pretty once the summer rolls around.
Marcelo Mayer is eventually going to be handed the reins at second base, maybe sooner rather than later, says @TheRealJPap58.
— Foul Territory (@FoulTerritoryTV) March 27, 2026
"They're going to want to see what he can do every day." pic.twitter.com/UkmcCLUrFm
Marcelo Mayer needs to display more consistency before Red Sox can fully trust him
The plate discipline part of Papelbon's comments are more salient than ever after an opening series in which both the best and worst parts of Mayer's game were on full display.
In his nine plate appearances against the Reds, he hit .333/.333/.556, good for a 142 wRC+. He wasn't in the Opening Day starting lineup since southpaw Andrew Abbott was the opposing pitcher, but Mayer came off the bench and produced two clutch hits in relief of platoon partner Isiah Kiner-Falefa (which he did again in the first game against the Houston Astros).
The problem? His slash line has dropped to .200/.294/.333 over six games because of some ugly chase (31.9%) and strikeout (35.3%) numbers. That's an unsustainable profile at the major-league level, even if he does hit the ball hard practically every time he makes contact.
In order to usurp Kiner-Falefa (and Andruw Monasterio) for more playing time, Mayer will have to hit lefties better. And he isn't going to do that until he puts the bat on the ball more often and shows more maturity at the plate; in his 27 career appearances against left-handed pitchers, he's struck out 37% of the time while walking just once.
The defense, as expected, was rock solid at second base in the opening series. Ditto for his baserunning. The pieces are all there for Mayer to start on an everyday basis in Boston — he just has to clean up the most frustrating part of his game to get there.