Yamamoto (forearm) is expected to throw a bullpen session within the next few days, Joe Frisaro of MLB.com reports.
Once Yamamoto gets back on the mound, the Marlins will reassess his likelihood of pitching again before the regular season wraps up Sept. 29. Assuming Yamamoto's bullpen session goes well, manager Don Mattingly said he expects the rookie to pitch a simulated game in the Marlins' fall instructional league before returning from the 10-day injured list. Yamomoto has been on the shelf since Aug. 28 with a right forearm strain.