Marcelo Mayer, who was promoted from Double-A Portland to Triple-A Worcester on Aug. 11, has been placed on the injured list on Tuesday. Derek Davis/Staff Photographer

Marcelo Mayer, one of the Boston Red Sox top prospects, will be placed on Triple-A Worcester’s injured list, a source confirmed to masslive.com.

The 21-year-old shortstop has been dealing with a lower back and upper glute muscle issue.

Mayer, who Boston promoted to Worcester along with Roman Anthony and Kyle Teel on Aug. 11, has not yet played in a game with the WooSox.

He last played in a game July 30 with Double-A Portland. He spent from Aug. 1-9 on Portland’s IL before being activated and promoted to Triple A.

Boston selected Mayer with the fourth overall pick in the 2021 MLB Draft. He batted .307 with a .370 on-base percentage, .480 slugging percentage, .850 OPS, eight homers, 28 doubles, 38 RBI and 60 runs in 77 games (335 plate appearances) for Portland this season.

“I’m feeling much better,” Mayer said Aug. 13. “My lower back and my upper glute was just bothering me a little bit. I missed a week in Somerset due to pec soreness and then my back kind of flared up on me. So we’ve just kind of been being cautious with it.”

Mayer and the Red Sox do not want him to play through the soreness and make it worse.

Injuries are becoming a concerning pattern for the organization’s No. 1 prospect. In 2022, right-wrist and back issues limited his first full professional season to 91 games. Last year, a shoulder impingement limited Mayer to 78 games between High-A Salem and Double-A, and ultimately cost him the last six weeks of the season. Between mid-June and late July this year, he missed games due to soreness in his left lower leg, back discomfort and pectoral soreness.

Now, Mayer is dealing with an injury that popped up while he was still in Portland and was expected to only take the minimum IL stay. The injury has lingered for most the month and it has put the rest of his season in jeopardy. The minor league season wraps up one week before the Red Sox’s regular-season finale on Sept. 29.

THE RED SOX released first baseman Dominic Smith, four days after they designated him for assignment. He is now a free agent.

Boston DFA’d the left-handed hitting Smith when lefty first baseman Triston Casas was reinstated from the 60-day injured list.

Smith batted .237 with a .317 on-base percentage, .390 slugging percentage, .706 OPS, 34 RBI and 29 runs in 83 games (278 plate appearances).

The 29-year-old initially signed with Boston on May 1, 11 days after Casas went on the IL with fractured cartilage which connects his ribcage to his sternum. Smith opted out of a minor league deal with the Rays before signing with the Red Sox.