Multiple reports say Yankees infielder Amed Rosario is experiencing a downturn specifically against left-handed pitching. The New York Post and Yahoo Sports both note that the Yankees had positioned Rosario as a “lefty killer” after bringing him back to face more left-handed matchups early in the season. In the first part of the year, the coverage describes Rosario as performing well in those situations. More recently, both outlets say he is “suddenly” struggling against lefties, describing the change as occurring at an unfavorable time for the Yankees’ overall offensive needs. The articles frame the issue as a shift from earlier success against left-handed opponents to a more difficult stretch, without detailing specific game logs or statistical measures in the provided excerpts. Overall, the reports agree that Rosario’s earlier matchup advantage versus left-handers has diminished and that this regression is emerging when the Yankees would benefit most from consistent production.