When Is Marcelo Mayer Getting Called Up? Fantasy Baseball Prospect Outlook (Week 7 Update)

When is Marcelo Mayer getting called up? Will Mayer get promoted in May 2025? Read about this top fantasy baseball prospect outlook heading into Week 7.

Boston Red Sox top prospect Marcelo Mayer seems to be getting close to making his Major League debut. Mayer's well-rounded game has helped him to rise quickly through the minors and kept him near the top of the top prospects list throughout the last few seasons. He's almost ready to make an impact in the majors after a strong showing in Triple-A this season.

As a result, Mayer is definitely someone fantasy managers should have on their radar at this point in the season, especially if you're in need of help in the infield. He doesn't have one stand-out tool, but should be able to contribute solid production across the board.

But when are the Red Sox going to call up Mayer? Can we expect him to make his debut in May? Let's dive in and find out. 

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Marcelo Mayer Prospect Update for Fantasy Baseball

The Red Sox drafted with the No. 4 pick in the 2021 MLB Draft out of high school. MLB Pipeline ranked him as the No. 8 overall prospect in baseball this season after he was No. 15 at the end of last year. The 22-year-old has steadily climbed through the minors despite battling a few injuries.

He spent 2024 in Double-A with the Portland Sea Dogs and hit .307 with eight home runs, 13 stolen bases, and a .383 wOBA in 77 games. He built on that success with a strong spring training this season, hitting .333 with a home run and a .435 wOBA in 20 games.

The Red Sox chose Kristian Campbell at 2B in the majors to start the season, while Mayer headed to Triple-A Worcester. In his 38 games, Mayer has hit .268 with a .362 wOBA, a stolen base, and 39 RBI in 38 games. He has already matched his total from last season with eight home runs as well.

Marcelo Mayer delivers in the clutch🫡

MLB’s No. 12 prospect hits a three-run blast in the ninth inning for the @WooSox.

(🎥@WooSox)
pic.twitter.com/pxTHTQH39D

— Baseball America (@BaseballAmerica) May 14, 2025

Mayer has handled velocity well and consistently made solid contact. According to Statcast, he has a 48.7% hard-hit rate and a 90.3 miles per hour average exit velocity.

Marcelo Mayer Outlook for Fantasy Baseball

Mayer looks ready for his MLB debut, but the Red Sox need to find him a place to play on a regular basis. With veteran Trevor Story currently the team's everyday shortstop, the team seems to be getting creative with their roster after losing starting first baseman Triston Casas to injury for the season.

Kristian Campbell was seen getting reps at first base this afternoon.

Marcelo Mayer is playing second base tonight in Worcester.

Maybe this becomes a thing... pic.twitter.com/L9pOCdVMsh

— Eric Cross (@EricCrossMLB) May 16, 2025

Mayer has the defensive versatility to slide to second base if needed, and Story has also played there in the past with the Red Sox if they choose to leave Mayer at shortstop. Story could also slide into a utility role since his bat has been unimpressive this season. He's hitting only .236 with six home runs, a .282 wOBA, and eight stolen bases in 44 games. Story is in the fourth year of a huge free-agent contract with a player opt-out after this season, with two more years before a club option in 2028.

Mayer has been playing more second base in Worcester, which could be enough to get him a promotion to the majors as soon as he's comfortable at that position and. Campbell is ready to move to first base or the outfield after his strong start to the season.

Fantasy managers who need help in the infield should be ready to add Mayer as soon as he gets promoted, or he can also be a solid stash if roster space is available. He should bring solid run production with decent home run and speed potential as a well-rounded, classic five-tool prospect.

Top Prospect Rankings and Call-Up ETAs

You can also check out the rest of RotoBaller's fantasy baseball prospect rankings. Eric Cross updates the below rankings weekly for the top impact prospects for 2025, and when they may be called up:

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