Chen (elbow) had a setback during his bullpen session Saturday, Joe Frisaro of MLB.com reports.

EDGE Analysis

The Marlins were encouraged following Chen's bullpen session Wednesday, but the lefty was forced to shut it down 15-20 pitches into Saturday's session due to renewed discomfort. It's uncertain what the plan is from here for Chen. He had been pitching through a partial UCL tear since the end of last season and receiving special treatment between each start.