Sherrill, 35, has made just two appearances this year and has been suffering elbow discomfort since spring training.
He's coming off a season in which he posted a 3.00 ERA in 36.0 innings for the Braves, although he missed most of the stretch drive because of elbow inflammation. Seattle signed him in December to a one-year, $1.1-million contract.
Johns notes that the loss of Sherrill means that Charlie Furbush and Rule-5 pick Lucas Luetge will work as the lone lefties in the Seattle bullpen.
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