Marcelo Mayer was drafted by the Red Sox 4th overall in the 2021 draft, falling to them after he was viewed as a top-three pick entering the draft. Some had even viewed him as the top prospect in that year's draft. In his senior season of high school, Mayer impressed many playing for Eastlake in California, putting up a slash line of .392/.555/.886 across 34 games to go along with good defense. Currently, Mayer stands at 6-foot-3 and weighs 188 pounds.

Since being drafted, there has been no doubt about Mayer’s potential, not just in the Red Sox organization but throughout baseball itself. He entered the 2022 season viewed as a consensus top-20 prospect and even as a top-10 prospect entering 2023. However, despite his intriguing skill set and potential, Mayer has been hit with a string of injuries since the 2022 season, which has limited his playtime.

In four seasons within the Red Sox organization, Mayer has played in 272 games, slashing .274/.362/.465. His 2024 season saw him perform well for the Portland Sea Dogs before it ended due to an injury. In that time, he played 77 games for the Red Sox Double-A team and hit .307/.370/.480 with eight home runs and 38 RBI.

What to Like:
There’s a lot to like about Mayer as a player. When healthy, he has quite the skillset. His offense and defense are viewed as potentially above-average, with the worst-case scenario being just an average hit tool. On offense, Mayer possesses a fluid swing, a solid feel for hitting, and quick hands. His bat speed and bat control are also impressive and viewed as above average.

His raw power is a plus. The young shortstop already shows that he can drive the ball to all parts of the field and has been viewed as potentially having above-average game power once he reaches his prime.

Mayer’s defense is where he might shine, however. Viewed as being a potentially plus defender at shortstop, Mayer moves well as he sometimes looks like he’s gliding on the field. With soft hands and solid footwork, he can move well and has plenty of range for a shortstop, especially at his size. To go with his fielding ability is a plus arm that allows him to make throws with plenty of zip.

What to Work On:
The big one for Mayer is to stay healthy. While it’s hard to control injuries, there is no doubt in many Red Sox fans’ minds that Mayer has been rather injury prone during his time with Boston. Across his first three full seasons, he has never played more than 91 games and last season he played in his least at 77 games. In 2022 he missed roughly a month from a wrist sprain and in 2023 he suffered a shoulder injury while sliding in early May. Despite only missing a week from that injury, it still lingered and affected his performance until he was placed on the injured list in early August and missed the rest of the season. 2024 was much of the same as he managed to play in 77 games before being placed on the injured list on August 1st while still playing for Portland. This time it was a lumbar injury which would keep him out for the remainder of the season despite a promotion to Worcester on August 11th alongside his fellow teammates Kyle Teel and Roman Anthony.

Offensively Mayer has some work to do when it comes to pitch recognition and tighten up his approach. While his skillset has the potential to be average to above-average, he currently leaves himself vulnerable against soft stuff. He did improve upon this issue in 2024 compared to 2023, but he still needs to continue to improve on it compared to how he handles fastballs. Because of this, there are some questions on how his contact skills will translate to more advanced pitching. He will also need to add strength to his game and he could see a lot of doubles turn into home runs in the future.

What’s Next:
Assuming Mayer starts Spring Training healthy, there is no reason to doubt he’ll get an invite to spring training as a non-roster invitee. The Red Sox will want to get a good look at his skillset and see how he’s developing not just skill wise but also when it comes to durability. However, much like Teel and other prospects on this list, do not be surprised if his name is included in mock trades. Despite his injuries Mayer is still an incredibly talented player that teams will be willing to take a chance on and the Red Sox will likely see if he could bring an ace in return in a trade.

Mayer’s floor is that of an above-average shortstop, his defense helping him stay in the lineup even if his offense never develops to its full potential. However, his ceiling is that of a regular All-Star, an everyday shortstop that has the offensive skills to hit at the top of a contenting team’s lineup. Many scouts believe he could be a four-tool player if everything develops to their full potential.

However, much like the other prospects we’ve discussed this offseason, it is unlikely that Mayer will break camp with the Red Sox barring a historic spring or an injury to one of the middle infielders already on the team. More likely, Mayer will begin the season with Worcester and get his first official taste of Triple-A after being unable to play following his promotion there in August. Unless traded, I wouldn’t be surprised if Mayer got a call up to the majors at some point this season unless he suffers another injury or struggles against the competition.