The Miami Marlins are reportedly designating infielders Ronny Simon and Matt Mervis for assignment, Craig Mish of SportsGrid reports.

“My understanding is the Marlins have several roster moves ahead of this weekend’s home series against the Giants. Those will include both Infielders Matt Mervis and Ronny Simon being designated for assignment,” Mish wrote on X, formerly Twitter.

Jon Heyman of The New York Post confirmed the report and revealed that infielder Jack Winkler is being promoted and infielder Dane Myers is returning to the big league ball club.

The decision to designate Simon comes after his multi-error game against the San Diego Padres. The 25-year-old slashed .234/.327/.277 across 19 games played with the Marlins in 2025.

Mervis, meanwhile, hit .175/.254/.383 in his 42 games with Miami this season. He previously played in MLB with the Chicago Cubs during the 2023 and 2024 seasons.

The Marlins are struggling once again during the '25 campaign. Miami currently holds a lackluster 22-32 record. As a result, the Marlins are in last place in the competitive National League East.

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The team's rebuild continues and it remains to be seen when they will emerge as a contender. Miami's core of players has yet to display true signs of contending potential. The unfortunate reality of the situation is the Marlins' rebuild may last for years to come.

Star pitcher Sandy Alcantara is expected to be a popular trade candidate ahead of the deadline in July. The 2022 National League Cy Young winner has struggled in 2025, but he is still likely going to draw plenty of interest from contending teams.

A potential Sandy Alcantara deal would be yet another move amid the Marlins' lengthy rebuild.

For now, the team will focus on Friday's game against the San Francisco Giants. First pitch is scheduled for 7:10 PM EST in Miami as the Marlins look to take care of business at home.