September rosters expanded to 28, and a flurry of callups and debuts reshapes fantasy value for the final month. Jordan Lawlar and Sal Stewart headline the prospects promoted by Arizona and Cincinnati, while Kevin Alcántara and George Valera are newly in-season fixtures with Cubs and Guardians. Payton Tolley and Jonah Tong delivered electric debuts for the Pirates and Mets rivalry week, and Sandy Alcantara is back to the form that boosted fantasy rosters all season. The Mets ride Juan Soto’s torrid stretch as their offense surges, and rosters churn continues with more rookies joining the mix as teams chase playoff spots.

Promoted hitters and pitchers mix with injury notes and bullpen shuffles, adding depth but also risk for fantasy owners. Masyn Winn’s health and return to action for St. Louis, plus Drew Gilbert's fresh look with the Giants, spotlight the evolving landscape of September value. The waiver wire stays active as veterans and rookies alike push for at-bats, with Cal Raleigh and other backstops offering streaming potential in deeper formats.