Acuña Jr. starts minor-league rehab as MLB injury picture shifts, while Nick Kurtz is sidelined

In this week’s MLB injury roundup, Ronald Acuña Jr. took what the league beat described as his next step toward returning to the Atlanta lineup, beginning a minor-league rehab assignment on Monday. Rehab assignments are typically used to test a player’s health and timing against game conditions before a major-league activation. For Braves followers, the immediate focus is less on the eventual date of a return and more on how Acuña performs as he works through the early portion of that process.

The injury report also referenced Kyle Harrison, describing that he has downplayed elbow soreness that had ultimately landed him on the injured list to end the first half of the season. Elbow discomfort can be a tricky category in baseball because even when symptoms appear manageable, teams often use conservative timelines to prevent setbacks. The reported point here is that Harrison’s own framing of the situation was more reassuring than the placement on the IL might suggest, but the team’s medical caution remains the controlling factor.

For the Athletics, Nick Kurtz is listed as sidelined with a thumb strain. A strained thumb can affect several aspects of performance, even without dramatic visible symptoms, including grip strength on the bat, the feel of pitches during hitting at-bats, and hand positioning during swings. When a middle-of-the-order or impact hitter sits, it can force late-inning depth and platoon balance to shift, particularly during stretches where matchups and lineup continuity matter.

Across the league, these types of injury updates tend to have a cascading effect. When one hitter begins a rehab assignment, it creates both a roster question and an opportunity for a replacement to make an impression, even if only temporarily. When a pitcher is managing an injury with uncertainty around how it will play out over the long term, it often changes bullpen usage patterns and affects how aggressively a club will push remaining starters between rest days.

The Athletics’ thumb-strain situation, meanwhile, likely has a more immediate effect on day-to-day offense, because a strain of this type can limit at-bats and alter how quickly a player can return to full swings. Without additional details, the key takeaway is the status change itself, which indicates that Oakland expects the issue to require time rather than simple rest.

What to watch next is straightforward but important: whether Acuña’s rehab steps progress without interruption, whether Harrison’s elbow soreness remains controlled as he works back into baseball activities, and how Oakland chooses to fill Kurtz’s at-bats in the meantime. Even in a season where teams manage injuries constantly, the teams that handle these midstream changes most effectively are often the ones that protect their rotation and lineup rhythm.

For readers trying to interpret the report, the most useful approach is to treat rehab assignments and IL designations as separate indicates. A rehab assignment generally indicates improved status, but it still requires confirmation through games. A player who is on the IL due to symptoms, even if they are characterized as downplayed, still carries a reactivity risk that can reshape schedules quickly.