Chen is entering the third season of an $80 million, five-year contract.
A balky left elbow limited Chen to nine games last year and 22 in 2016. He was a durable starter with Baltimore and has a career record of 53-38 in six seasons, but is only 7-6 with the Marlins.
Chen began a throwing program in mid-January, and the Marlins won't rush his return, manager Don Mattingly said Wednesday.
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